diff --git a/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.xml b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.xml
new file mode 100644
index 0000000..bf58a15
--- /dev/null
+++ b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.xml
@@ -0,0 +1,124 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
+    xmlns:alg="urn:oasis:names:tc:SAML:metadata:algsupport"
+    xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
+    xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol"
+    xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init"
+    xmlns:mdattr="urn:oasis:names:tc:SAML:metadata:attribute"
+    xmlns:mdrpi="urn:oasis:names:tc:SAML:metadata:rpi"
+    xmlns:mdui="urn:oasis:names:tc:SAML:metadata:ui"
+    xmlns:remd="http://refeds.org/metadata"
+    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
+    xmlns:shibmd="urn:mace:shibboleth:metadata:1.0"
+    xmlns:ukfedlabel="http://ukfederation.org.uk/2006/11/label"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="urn:oasis:names:tc:SAML:2.0:metadata saml-schema-metadata-2.0.xsd
+        urn:oasis:names:tc:SAML:metadata:algsupport sstc-saml-metadata-algsupport-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:attribute sstc-metadata-attr.xsd
+        urn:oasis:names:tc:SAML:metadata:rpi saml-metadata-rpi-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:ui sstc-saml-metadata-ui-v1.0.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol sstc-saml-idp-discovery.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:request-init sstc-request-initiation.xsd
+        urn:oasis:names:tc:SAML:2.0:assertion saml-schema-assertion-2.0.xsd
+        urn:mace:shibboleth:metadata:1.0 shibboleth-metadata-1.0.xsd
+        http://ukfederation.org.uk/2006/11/label uk-fed-label.xsd
+        http://refeds.org/metadata refeds-metadata.xsd
+        http://www.w3.org/2001/04/xmlenc# xenc-schema.xsd
+        http://www.w3.org/2009/xmlenc11# xenc-schema-11.xsd
+        http://www.w3.org/2000/09/xmldsig# xmldsig-core-schema.xsd"
+    ID="uk999999" entityID="https://idp.example.org/idp/shibboleth">
+
+    <Extensions>
+        <ukfedlabel:UKFederationMember orgID="ukforg9999"/>
+        <shibmd:Scope regexp="false">example.org</shibmd:Scope>
+        <ukfedlabel:Software date="2016-11-17" fullVersion="3.3.0" name="Shibboleth" version="3"/>
+        <ukfedlabel:ExportOptIn date="2009-09-11"/>
+        <mdrpi:RegistrationInfo registrationAuthority="http://ukfederation.org.uk"
+            registrationInstant="2007-03-30T16:36:00Z">
+            <mdrpi:RegistrationPolicy xml:lang="en"
+                >http://ukfederation.org.uk/doc/mdrps-20130902</mdrpi:RegistrationPolicy>
+        </mdrpi:RegistrationInfo>        
+    </Extensions>
+    <SPSSODescriptor protocolSupportEnumeration="urn:oasis:names:tc:SAML:2.0:protocol urn:oasis:names:tc:SAML:1.1:protocol">
+            <Extensions>
+                <init:RequestInitiator xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Binding="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Location="https://sp.example.org/Shibboleth.sso/Login"/>
+                <idpdisc:DiscoveryResponse xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Binding="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Location="https://sp.example.org/Shibboleth.sso/Login" index="1"/>
+                <mdui:UIInfo>
+                    <mdui:Logo height="68" width="240">https://sp.example.org/strip-non-äscii.jpg</mdui:Logo>
+                    <mdui:DisplayName xml:lang="en">Test SPSSODescriptor</mdui:DisplayName>
+                </mdui:UIInfo>                
+            </Extensions>            
+            <KeyDescriptor use="encryption">
+                <ds:KeyInfo>
+                    <ds:X509Data>
+                        <ds:X509SubjectName>CN=example.org,DC=example,DC=org</ds:X509SubjectName>
+                        <ds:X509Certificate>
+                            MIIFqTCCA5GgAwIBAgIUHWEbwHJ4qTTl9Tc/iU5fXjFnAEIwDQYJKoZIhvcNAQEL
+                            BQAwZDELMAkGA1UEBhMCR0IxEDAOBgNVBAgMB0JyaXN0b2wxEDAOBgNVBAcMB0Jy
+                            aXN0b2wxDTALBgNVBAoMBEppc2MxDDAKBgNVBAsMA1QmSTEUMBIGA1UEAwwLZXhh
+                            bXBsZS5vcmcwHhcNMjMwNzE3MDgxNzQ5WhcNNDMwNzEyMDgxNzQ5WjBkMQswCQYD
+                            VQQGEwJHQjEQMA4GA1UECAwHQnJpc3RvbDEQMA4GA1UEBwwHQnJpc3RvbDENMAsG
+                            A1UECgwESmlzYzEMMAoGA1UECwwDVCZJMRQwEgYDVQQDDAtleGFtcGxlLm9yZzCC
+                            AiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAKhcZPLvOEkLTTDyVRVhXz2q
+                            bME+1DkMdg8JL123KcuGxucz7sorF9pj7SC94aWlic4sQ54O4/2X8CzL4yGDThuL
+                            opuTeB5QPD+y/xuvV8Il1CdG3MXzTAjFP3Oa2ggZKktWIkW2T0f8uVzpWhddP4Aa
+                            sp5uKbF7qDRs6TwUHhllhiXlDcSfbW5N8+LeS+15qoJzVha9og9D6wwNhThigcLw
+                            9muP8L6KkL+ATGz+ArvkOoC5bMueO8NM5iDlAUtNxviPzbqLtcufrAYm+lV2hwCo
+                            nKmAEvNQ6D0jhSxlyDl8/VYU9nwmV1cKETNfJi3zkMO6s/47tvHP0JbFF0tFPixI
+                            PbIh5jPT+U1CbzEzG62QUrNXYnueqR9x9iVeygjzM/Jc2u1Jh+amlUMjWI9SmYt9
+                            dRf4Y+6rtWdwVMi+5fDF/f2G7VR7kZNTHJgoCll/U4CuQ4dqhtDh/Wdr6ABfx/ao
+                            FcmjEhHCNw1aS55CcmqZj8GDSJPTGb/N2h3Zy2IrBqwp8JZom8ERlpYj2H5B1Gi5
+                            Ue26jnyO3DAi6aCN09RcZS8OZWOtFTjJ1d9Knv4kFtcOOV61wVsURJ8lV6oMelSw
+                            Qabl6/AqHfC7GP4rGNZHnAZa58YRBRCov+AZjip9IGY+YWKCl5zPYDVWfZMKQmST
+                            NoE2hw9WR287j23QIviHAgMBAAGjUzBRMB0GA1UdDgQWBBR/zhqQSzIXEraLCetw
+                            7M3ZHt4WIzAfBgNVHSMEGDAWgBR/zhqQSzIXEraLCetw7M3ZHt4WIzAPBgNVHRMB
+                            Af8EBTADAQH/MA0GCSqGSIb3DQEBCwUAA4ICAQBlMlkz+jLyvonTufDzdqjv/6QY
+                            aANnPcIXAmmxTFlJOHOGf982pfXixFNt1c7wCs6PpQWVKoFGrhDO9IwIrgxgUY/+
+                            aLA/MKh8a2Sk9JYqA4YC6kNBb+jkWZalfOSNlQNoEGLKneEq+u2QN2RMELBSHwZD
+                            jqItaV4Ovfdmx3x6jSuRqsZ8yCl0KrqziwvoYPhdQBXjbrOwA/0nwOGn8RohEGfD
+                            FmRQwA0YfKtdIVCmMhpCV0guh4QMmviiJF/xMZNGRk/VhMyLfYvtRzqhL72MB8cf
+                            l9a56vhf/wk84GnOKyh0xXJdyxfeT3daATTi/suLG/mwnWR1WxHQpDIHv1rYZUj7
+                            5KCmSaD1XbZh2H+D2GVCC4LBZpR/HVej96kdr+RWLDl4leM0Mdi/IbqMFLur6te0
+                            IQD9BY585aec4lTkcSo3VY5HXvHC00G1xya48Q2sySCl8XY0gbV7rMh3Qf5ziBX6
+                            GiVAnYCkFVAza4qMyYKshqbLXOP+Zh/1gCstCGdYi4vBt4goe3Xpu2jtrJiLr9m1
+                            Jhk/Qm7A+S0vjXtShuaecfcd8mXSqZJ8G4yIcQxqF6cMwBVWl059LOrRYQ1UPeZx
+                            6/vfb7EfKuQfFOtHHdF5N9DTGIqBxjcq/SIZnD1ji5ftl+lDUzOaMS82wMBwFJ/r
+                            IrhKy4GrwvGT/y1q8Q==
+                           </ds:X509Certificate>
+                    </ds:X509Data>
+                </ds:KeyInfo>
+            </KeyDescriptor>            
+            <ArtifactResolutionService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/Artifact/SOAP" index="0"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SLO/Artifact"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SLO/POST"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect" Location="https://sp.example.org/Shibboleth.sso/SLO/Redirect"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/SLO/SOAP"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:artifact-01" Location="https://sp.example.org/Shibboleth.sso/SAML/Artifact" index="0"/>
+
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:browser-post" Location="https://sp.example.org/Shibboleth.sso/SAML/POST" index="1"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SAML2/Artifact" index="2"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:PAOS" Location="https://sp.example.org/Shibboleth.sso/SAML2/ECP" index="3"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST" index="4"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST-SimpleSign" index="5"/>
+    </SPSSODescriptor>
+    <Organization>
+        <OrganizationName xml:lang="en">An Example Organization</OrganizationName>
+        <OrganizationDisplayName xml:lang="en">An Example Organization</OrganizationDisplayName>
+        <OrganizationURL xml:lang="en">http://example.org/</OrganizationURL>
+    </Organization>
+    <ContactPerson contactType="support">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="technical">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="administrative">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:anexample@example.org</EmailAddress>
+    </ContactPerson>
+</EntityDescriptor>
diff --git a/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.yaml b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.yaml
new file mode 100644
index 0000000..da780a9
--- /dev/null
+++ b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii.yaml
@@ -0,0 +1,4 @@
+expected:
+    - status: error
+      component_id: check_mdui_logo_url/non-ascii
+      message: mdui:Logo contains non-ascii characters
diff --git a/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii_non_subset.xml b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii_non_subset.xml
new file mode 100644
index 0000000..2947192
--- /dev/null
+++ b/tests/xml/mdui/bad_mdui_uiinfo_logo_non_ascii_non_subset.xml
@@ -0,0 +1,125 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
+    xmlns:alg="urn:oasis:names:tc:SAML:metadata:algsupport"
+    xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
+    xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol"
+    xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init"
+    xmlns:mdattr="urn:oasis:names:tc:SAML:metadata:attribute"
+    xmlns:mdrpi="urn:oasis:names:tc:SAML:metadata:rpi"
+    xmlns:mdui="urn:oasis:names:tc:SAML:metadata:ui"
+    xmlns:remd="http://refeds.org/metadata"
+    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
+    xmlns:shibmd="urn:mace:shibboleth:metadata:1.0"
+    xmlns:ukfedlabel="http://ukfederation.org.uk/2006/11/label"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="urn:oasis:names:tc:SAML:2.0:metadata saml-schema-metadata-2.0.xsd
+        urn:oasis:names:tc:SAML:metadata:algsupport sstc-saml-metadata-algsupport-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:attribute sstc-metadata-attr.xsd
+        urn:oasis:names:tc:SAML:metadata:rpi saml-metadata-rpi-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:ui sstc-saml-metadata-ui-v1.0.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol sstc-saml-idp-discovery.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:request-init sstc-request-initiation.xsd
+        urn:oasis:names:tc:SAML:2.0:assertion saml-schema-assertion-2.0.xsd
+        urn:mace:shibboleth:metadata:1.0 shibboleth-metadata-1.0.xsd
+        http://ukfederation.org.uk/2006/11/label uk-fed-label.xsd
+        http://refeds.org/metadata refeds-metadata.xsd
+        http://www.w3.org/2001/04/xmlenc# xenc-schema.xsd
+        http://www.w3.org/2009/xmlenc11# xenc-schema-11.xsd
+        http://www.w3.org/2000/09/xmldsig# xmldsig-core-schema.xsd"
+    ID="uk999999" entityID="https://idp.example.org/idp/shibboleth">
+
+    <Extensions>
+        <ukfedlabel:UKFederationMember orgID="ukforg9999"/>
+        <shibmd:Scope regexp="false">example.org</shibmd:Scope>
+        <ukfedlabel:Software date="2016-11-17" fullVersion="3.3.0" name="Shibboleth" version="3"/>
+        <ukfedlabel:ExportOptIn date="2009-09-11"/>
+        <mdrpi:RegistrationInfo registrationAuthority="http://ukfederation.org.uk"
+            registrationInstant="2007-03-30T16:36:00Z">
+            <mdrpi:RegistrationPolicy xml:lang="en"
+                >http://ukfederation.org.uk/doc/mdrps-20130902</mdrpi:RegistrationPolicy>
+        </mdrpi:RegistrationInfo>        
+    </Extensions>
+    <SPSSODescriptor protocolSupportEnumeration="urn:oasis:names:tc:SAML:2.0:protocol urn:oasis:names:tc:SAML:1.1:protocol">
+            <Extensions>
+                <init:RequestInitiator xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Binding="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Location="https://sp.example.org/Shibboleth.sso/Login"/>
+                <idpdisc:DiscoveryResponse xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Binding="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Location="https://sp.example.org/Shibboleth.sso/Login" index="1"/>
+                <mdui:UIInfo>
+                    <!-- Characters within the ASCII range but outside the set used for URIs (which is a subset of ASCII)-->
+                    <mdui:Logo height="68" width="240">https://sp.example.org/strip-non-ascii^.jpg</mdui:Logo>
+                    <mdui:DisplayName xml:lang="en">Test SPSSODescriptor</mdui:DisplayName>
+                </mdui:UIInfo>                
+            </Extensions>            
+            <KeyDescriptor use="encryption">
+                <ds:KeyInfo>
+                    <ds:X509Data>
+                        <ds:X509SubjectName>CN=example.org,DC=example,DC=org</ds:X509SubjectName>
+                        <ds:X509Certificate>
+                            MIIFqTCCA5GgAwIBAgIUHWEbwHJ4qTTl9Tc/iU5fXjFnAEIwDQYJKoZIhvcNAQEL
+                            BQAwZDELMAkGA1UEBhMCR0IxEDAOBgNVBAgMB0JyaXN0b2wxEDAOBgNVBAcMB0Jy
+                            aXN0b2wxDTALBgNVBAoMBEppc2MxDDAKBgNVBAsMA1QmSTEUMBIGA1UEAwwLZXhh
+                            bXBsZS5vcmcwHhcNMjMwNzE3MDgxNzQ5WhcNNDMwNzEyMDgxNzQ5WjBkMQswCQYD
+                            VQQGEwJHQjEQMA4GA1UECAwHQnJpc3RvbDEQMA4GA1UEBwwHQnJpc3RvbDENMAsG
+                            A1UECgwESmlzYzEMMAoGA1UECwwDVCZJMRQwEgYDVQQDDAtleGFtcGxlLm9yZzCC
+                            AiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAKhcZPLvOEkLTTDyVRVhXz2q
+                            bME+1DkMdg8JL123KcuGxucz7sorF9pj7SC94aWlic4sQ54O4/2X8CzL4yGDThuL
+                            opuTeB5QPD+y/xuvV8Il1CdG3MXzTAjFP3Oa2ggZKktWIkW2T0f8uVzpWhddP4Aa
+                            sp5uKbF7qDRs6TwUHhllhiXlDcSfbW5N8+LeS+15qoJzVha9og9D6wwNhThigcLw
+                            9muP8L6KkL+ATGz+ArvkOoC5bMueO8NM5iDlAUtNxviPzbqLtcufrAYm+lV2hwCo
+                            nKmAEvNQ6D0jhSxlyDl8/VYU9nwmV1cKETNfJi3zkMO6s/47tvHP0JbFF0tFPixI
+                            PbIh5jPT+U1CbzEzG62QUrNXYnueqR9x9iVeygjzM/Jc2u1Jh+amlUMjWI9SmYt9
+                            dRf4Y+6rtWdwVMi+5fDF/f2G7VR7kZNTHJgoCll/U4CuQ4dqhtDh/Wdr6ABfx/ao
+                            FcmjEhHCNw1aS55CcmqZj8GDSJPTGb/N2h3Zy2IrBqwp8JZom8ERlpYj2H5B1Gi5
+                            Ue26jnyO3DAi6aCN09RcZS8OZWOtFTjJ1d9Knv4kFtcOOV61wVsURJ8lV6oMelSw
+                            Qabl6/AqHfC7GP4rGNZHnAZa58YRBRCov+AZjip9IGY+YWKCl5zPYDVWfZMKQmST
+                            NoE2hw9WR287j23QIviHAgMBAAGjUzBRMB0GA1UdDgQWBBR/zhqQSzIXEraLCetw
+                            7M3ZHt4WIzAfBgNVHSMEGDAWgBR/zhqQSzIXEraLCetw7M3ZHt4WIzAPBgNVHRMB
+                            Af8EBTADAQH/MA0GCSqGSIb3DQEBCwUAA4ICAQBlMlkz+jLyvonTufDzdqjv/6QY
+                            aANnPcIXAmmxTFlJOHOGf982pfXixFNt1c7wCs6PpQWVKoFGrhDO9IwIrgxgUY/+
+                            aLA/MKh8a2Sk9JYqA4YC6kNBb+jkWZalfOSNlQNoEGLKneEq+u2QN2RMELBSHwZD
+                            jqItaV4Ovfdmx3x6jSuRqsZ8yCl0KrqziwvoYPhdQBXjbrOwA/0nwOGn8RohEGfD
+                            FmRQwA0YfKtdIVCmMhpCV0guh4QMmviiJF/xMZNGRk/VhMyLfYvtRzqhL72MB8cf
+                            l9a56vhf/wk84GnOKyh0xXJdyxfeT3daATTi/suLG/mwnWR1WxHQpDIHv1rYZUj7
+                            5KCmSaD1XbZh2H+D2GVCC4LBZpR/HVej96kdr+RWLDl4leM0Mdi/IbqMFLur6te0
+                            IQD9BY585aec4lTkcSo3VY5HXvHC00G1xya48Q2sySCl8XY0gbV7rMh3Qf5ziBX6
+                            GiVAnYCkFVAza4qMyYKshqbLXOP+Zh/1gCstCGdYi4vBt4goe3Xpu2jtrJiLr9m1
+                            Jhk/Qm7A+S0vjXtShuaecfcd8mXSqZJ8G4yIcQxqF6cMwBVWl059LOrRYQ1UPeZx
+                            6/vfb7EfKuQfFOtHHdF5N9DTGIqBxjcq/SIZnD1ji5ftl+lDUzOaMS82wMBwFJ/r
+                            IrhKy4GrwvGT/y1q8Q==
+                           </ds:X509Certificate>
+                    </ds:X509Data>
+                </ds:KeyInfo>
+            </KeyDescriptor>            
+            <ArtifactResolutionService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/Artifact/SOAP" index="0"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SLO/Artifact"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SLO/POST"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect" Location="https://sp.example.org/Shibboleth.sso/SLO/Redirect"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/SLO/SOAP"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:artifact-01" Location="https://sp.example.org/Shibboleth.sso/SAML/Artifact" index="0"/>
+
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:browser-post" Location="https://sp.example.org/Shibboleth.sso/SAML/POST" index="1"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SAML2/Artifact" index="2"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:PAOS" Location="https://sp.example.org/Shibboleth.sso/SAML2/ECP" index="3"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST" index="4"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST-SimpleSign" index="5"/>
+    </SPSSODescriptor>
+    <Organization>
+        <OrganizationName xml:lang="en">An Example Organization</OrganizationName>
+        <OrganizationDisplayName xml:lang="en">An Example Organization</OrganizationDisplayName>
+        <OrganizationURL xml:lang="en">http://example.org/</OrganizationURL>
+    </Organization>
+    <ContactPerson contactType="support">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="technical">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="administrative">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:anexample@example.org</EmailAddress>
+    </ContactPerson>
+</EntityDescriptor>
diff --git a/tests/xml/mdui/good_mdui_uiinfo_logo_non_ascii_onlyvalidchars.xml b/tests/xml/mdui/good_mdui_uiinfo_logo_non_ascii_onlyvalidchars.xml
new file mode 100644
index 0000000..15adf69
--- /dev/null
+++ b/tests/xml/mdui/good_mdui_uiinfo_logo_non_ascii_onlyvalidchars.xml
@@ -0,0 +1,125 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
+    xmlns:alg="urn:oasis:names:tc:SAML:metadata:algsupport"
+    xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
+    xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol"
+    xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init"
+    xmlns:mdattr="urn:oasis:names:tc:SAML:metadata:attribute"
+    xmlns:mdrpi="urn:oasis:names:tc:SAML:metadata:rpi"
+    xmlns:mdui="urn:oasis:names:tc:SAML:metadata:ui"
+    xmlns:remd="http://refeds.org/metadata"
+    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
+    xmlns:shibmd="urn:mace:shibboleth:metadata:1.0"
+    xmlns:ukfedlabel="http://ukfederation.org.uk/2006/11/label"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="urn:oasis:names:tc:SAML:2.0:metadata saml-schema-metadata-2.0.xsd
+        urn:oasis:names:tc:SAML:metadata:algsupport sstc-saml-metadata-algsupport-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:attribute sstc-metadata-attr.xsd
+        urn:oasis:names:tc:SAML:metadata:rpi saml-metadata-rpi-v1.0.xsd
+        urn:oasis:names:tc:SAML:metadata:ui sstc-saml-metadata-ui-v1.0.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol sstc-saml-idp-discovery.xsd
+        urn:oasis:names:tc:SAML:profiles:SSO:request-init sstc-request-initiation.xsd
+        urn:oasis:names:tc:SAML:2.0:assertion saml-schema-assertion-2.0.xsd
+        urn:mace:shibboleth:metadata:1.0 shibboleth-metadata-1.0.xsd
+        http://ukfederation.org.uk/2006/11/label uk-fed-label.xsd
+        http://refeds.org/metadata refeds-metadata.xsd
+        http://www.w3.org/2001/04/xmlenc# xenc-schema.xsd
+        http://www.w3.org/2009/xmlenc11# xenc-schema-11.xsd
+        http://www.w3.org/2000/09/xmldsig# xmldsig-core-schema.xsd"
+    ID="uk999999" entityID="https://idp.example.org/idp/shibboleth">
+
+    <Extensions>
+        <ukfedlabel:UKFederationMember orgID="ukforg9999"/>
+        <shibmd:Scope regexp="false">example.org</shibmd:Scope>
+        <ukfedlabel:Software date="2016-11-17" fullVersion="3.3.0" name="Shibboleth" version="3"/>
+        <ukfedlabel:ExportOptIn date="2009-09-11"/>
+        <mdrpi:RegistrationInfo registrationAuthority="http://ukfederation.org.uk"
+            registrationInstant="2007-03-30T16:36:00Z">
+            <mdrpi:RegistrationPolicy xml:lang="en"
+                >http://ukfederation.org.uk/doc/mdrps-20130902</mdrpi:RegistrationPolicy>
+        </mdrpi:RegistrationInfo>        
+    </Extensions>
+    <SPSSODescriptor protocolSupportEnumeration="urn:oasis:names:tc:SAML:2.0:protocol urn:oasis:names:tc:SAML:1.1:protocol">
+            <Extensions>
+                <init:RequestInitiator xmlns:init="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Binding="urn:oasis:names:tc:SAML:profiles:SSO:request-init" Location="https://sp.example.org/Shibboleth.sso/Login"/>
+                <idpdisc:DiscoveryResponse xmlns:idpdisc="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Binding="urn:oasis:names:tc:SAML:profiles:SSO:idp-discovery-protocol" Location="https://sp.example.org/Shibboleth.sso/Login" index="1"/>
+                <mdui:UIInfo>
+                    <!-- All these characters should be valid in URIs-->
+                    <mdui:Logo height="68" width="240">https://sp.example.org/ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&amp;'()*+,;=%23</mdui:Logo>
+                    <mdui:DisplayName xml:lang="en">Test SPSSODescriptor</mdui:DisplayName>
+                </mdui:UIInfo>                
+            </Extensions>            
+            <KeyDescriptor use="encryption">
+                <ds:KeyInfo>
+                    <ds:X509Data>
+                        <ds:X509SubjectName>CN=example.org,DC=example,DC=org</ds:X509SubjectName>
+                        <ds:X509Certificate>
+                            MIIFqTCCA5GgAwIBAgIUHWEbwHJ4qTTl9Tc/iU5fXjFnAEIwDQYJKoZIhvcNAQEL
+                            BQAwZDELMAkGA1UEBhMCR0IxEDAOBgNVBAgMB0JyaXN0b2wxEDAOBgNVBAcMB0Jy
+                            aXN0b2wxDTALBgNVBAoMBEppc2MxDDAKBgNVBAsMA1QmSTEUMBIGA1UEAwwLZXhh
+                            bXBsZS5vcmcwHhcNMjMwNzE3MDgxNzQ5WhcNNDMwNzEyMDgxNzQ5WjBkMQswCQYD
+                            VQQGEwJHQjEQMA4GA1UECAwHQnJpc3RvbDEQMA4GA1UEBwwHQnJpc3RvbDENMAsG
+                            A1UECgwESmlzYzEMMAoGA1UECwwDVCZJMRQwEgYDVQQDDAtleGFtcGxlLm9yZzCC
+                            AiIwDQYJKoZIhvcNAQEBBQADggIPADCCAgoCggIBAKhcZPLvOEkLTTDyVRVhXz2q
+                            bME+1DkMdg8JL123KcuGxucz7sorF9pj7SC94aWlic4sQ54O4/2X8CzL4yGDThuL
+                            opuTeB5QPD+y/xuvV8Il1CdG3MXzTAjFP3Oa2ggZKktWIkW2T0f8uVzpWhddP4Aa
+                            sp5uKbF7qDRs6TwUHhllhiXlDcSfbW5N8+LeS+15qoJzVha9og9D6wwNhThigcLw
+                            9muP8L6KkL+ATGz+ArvkOoC5bMueO8NM5iDlAUtNxviPzbqLtcufrAYm+lV2hwCo
+                            nKmAEvNQ6D0jhSxlyDl8/VYU9nwmV1cKETNfJi3zkMO6s/47tvHP0JbFF0tFPixI
+                            PbIh5jPT+U1CbzEzG62QUrNXYnueqR9x9iVeygjzM/Jc2u1Jh+amlUMjWI9SmYt9
+                            dRf4Y+6rtWdwVMi+5fDF/f2G7VR7kZNTHJgoCll/U4CuQ4dqhtDh/Wdr6ABfx/ao
+                            FcmjEhHCNw1aS55CcmqZj8GDSJPTGb/N2h3Zy2IrBqwp8JZom8ERlpYj2H5B1Gi5
+                            Ue26jnyO3DAi6aCN09RcZS8OZWOtFTjJ1d9Knv4kFtcOOV61wVsURJ8lV6oMelSw
+                            Qabl6/AqHfC7GP4rGNZHnAZa58YRBRCov+AZjip9IGY+YWKCl5zPYDVWfZMKQmST
+                            NoE2hw9WR287j23QIviHAgMBAAGjUzBRMB0GA1UdDgQWBBR/zhqQSzIXEraLCetw
+                            7M3ZHt4WIzAfBgNVHSMEGDAWgBR/zhqQSzIXEraLCetw7M3ZHt4WIzAPBgNVHRMB
+                            Af8EBTADAQH/MA0GCSqGSIb3DQEBCwUAA4ICAQBlMlkz+jLyvonTufDzdqjv/6QY
+                            aANnPcIXAmmxTFlJOHOGf982pfXixFNt1c7wCs6PpQWVKoFGrhDO9IwIrgxgUY/+
+                            aLA/MKh8a2Sk9JYqA4YC6kNBb+jkWZalfOSNlQNoEGLKneEq+u2QN2RMELBSHwZD
+                            jqItaV4Ovfdmx3x6jSuRqsZ8yCl0KrqziwvoYPhdQBXjbrOwA/0nwOGn8RohEGfD
+                            FmRQwA0YfKtdIVCmMhpCV0guh4QMmviiJF/xMZNGRk/VhMyLfYvtRzqhL72MB8cf
+                            l9a56vhf/wk84GnOKyh0xXJdyxfeT3daATTi/suLG/mwnWR1WxHQpDIHv1rYZUj7
+                            5KCmSaD1XbZh2H+D2GVCC4LBZpR/HVej96kdr+RWLDl4leM0Mdi/IbqMFLur6te0
+                            IQD9BY585aec4lTkcSo3VY5HXvHC00G1xya48Q2sySCl8XY0gbV7rMh3Qf5ziBX6
+                            GiVAnYCkFVAza4qMyYKshqbLXOP+Zh/1gCstCGdYi4vBt4goe3Xpu2jtrJiLr9m1
+                            Jhk/Qm7A+S0vjXtShuaecfcd8mXSqZJ8G4yIcQxqF6cMwBVWl059LOrRYQ1UPeZx
+                            6/vfb7EfKuQfFOtHHdF5N9DTGIqBxjcq/SIZnD1ji5ftl+lDUzOaMS82wMBwFJ/r
+                            IrhKy4GrwvGT/y1q8Q==
+                           </ds:X509Certificate>
+                    </ds:X509Data>
+                </ds:KeyInfo>
+            </KeyDescriptor>            
+            <ArtifactResolutionService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/Artifact/SOAP" index="0"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SLO/Artifact"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SLO/POST"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect" Location="https://sp.example.org/Shibboleth.sso/SLO/Redirect"/>
+            <SingleLogoutService Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP" Location="https://sp.example.org/Shibboleth.sso/SLO/SOAP"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:artifact-01" Location="https://sp.example.org/Shibboleth.sso/SAML/Artifact" index="0"/>
+
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:browser-post" Location="https://sp.example.org/Shibboleth.sso/SAML/POST" index="1"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.example.org/Shibboleth.sso/SAML2/Artifact" index="2"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:PAOS" Location="https://sp.example.org/Shibboleth.sso/SAML2/ECP" index="3"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST" index="4"/>
+            <AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://sp.example.org/Shibboleth.sso/SAML2/POST-SimpleSign" index="5"/>
+    </SPSSODescriptor>
+    <Organization>
+        <OrganizationName xml:lang="en">An Example Organization</OrganizationName>
+        <OrganizationDisplayName xml:lang="en">An Example Organization</OrganizationDisplayName>
+        <OrganizationURL xml:lang="en">http://example.org/</OrganizationURL>
+    </Organization>
+    <ContactPerson contactType="support">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="technical">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:ukfed@example.org</EmailAddress>
+    </ContactPerson>
+    <ContactPerson contactType="administrative">
+        <GivenName>An</GivenName>
+        <SurName>Example</SurName>
+        <EmailAddress>mailto:anexample@example.org</EmailAddress>
+    </ContactPerson>
+</EntityDescriptor>
diff --git a/validators/overlays/development/classes/development-stages.xml b/validators/overlays/development/classes/development-stages.xml
index 167ce97..cd68405 100644
--- a/validators/overlays/development/classes/development-stages.xml
+++ b/validators/overlays/development/classes/development-stages.xml
@@ -18,8 +18,21 @@
         <property name="stages">
             <util:list>
                 <!-- Under-development checks go here. -->
+                <ref bean="check_mdui_logo_url"/>
             </util:list>
         </property>
     </bean>
 
+    <!-- Add this back to the validation-beans.xml version when tested -->
+    <bean id="check_mdui_logo_url" parent="mda.StringElementValidationStage">
+        <property name="elementName" ref="mdui-Logo"/>
+        <property name="validators">
+            <list>
+                <bean p:id="non-ascii" parent="mda.RejectStringRegexValidator"
+                    p:regex=".*[^A-Za-z0-9\-._~:/?#\[\]@!$&amp;'()*+,;=%].*"
+                    p:message="mdui:Logo contains non-ascii characters" />
+            </list>
+        </property>
+    </bean>
+
 </beans>