diff --git a/includes/blocks.php b/includes/blocks.php
index fd2f9f0..7adbf56 100644
--- a/includes/blocks.php
+++ b/includes/blocks.php
@@ -7,6 +7,10 @@
 
 namespace SafeSvg\Blocks;
 
+if ( ! defined( 'ABSPATH' ) ) {
+	exit; // Exit if accessed directly.
+}
+
 /**
  * Set up blocks
  *
diff --git a/includes/optimizer.php b/includes/optimizer.php
index fe1cc81..acd96b9 100644
--- a/includes/optimizer.php
+++ b/includes/optimizer.php
@@ -9,6 +9,10 @@
 
 use enshrined\svgSanitize\Sanitizer;
 
+if ( ! defined( 'ABSPATH' ) ) {
+	exit; // Exit if accessed directly.
+}
+
 if ( ! class_exists( '\SafeSVG\Optimizer' ) ) {
 
 	/**
diff --git a/includes/safe-svg-settings.php b/includes/safe-svg-settings.php
index 05239b7..591a8d7 100644
--- a/includes/safe-svg-settings.php
+++ b/includes/safe-svg-settings.php
@@ -7,6 +7,10 @@
 
 namespace SafeSvg;
 
+if ( ! defined( 'ABSPATH' ) ) {
+	exit; // Exit if accessed directly.
+}
+
 /**
  * SVG settings class.
  */