diff --git a/.gitignore b/.gitignore
index 73d8e98..d350f0b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,7 @@
 /composer.phar
 /composer.lock
 /.phpunit.result.cache
+.env
+.env*
+/tests/env/
+.idea
\ No newline at end of file
diff --git a/composer.json b/composer.json
index fac18e5..517fc5d 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,8 @@
     },
     "require": {
         "php": ">=8.0",
-        "async-aws/ssm": "^1.3"
+        "async-aws/ssm": "^1.3",
+        "vlucas/phpdotenv": "^5.6"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.6.10",
diff --git a/src/Secrets.php b/src/Secrets.php
index 639e815..d4abd93 100644
--- a/src/Secrets.php
+++ b/src/Secrets.php
@@ -4,6 +4,7 @@
 
 use AsyncAws\Ssm\SsmClient;
 use Closure;
+use Dotenv\Dotenv;
 use JsonException;
 use RuntimeException;
 
@@ -17,11 +18,7 @@ class Secrets
      */
     public static function loadSecretEnvironmentVariables(?SsmClient $ssmClient = null): void
     {
-        /** @var array<string,string>|string|false $envVars */
-        $envVars = getenv(local_only: true); // @phpstan-ignore-line PHPStan is wrong
-        if (! is_array($envVars)) {
-            return;
-        }
+        $envVars = self::getEnvVars();
 
         // Only consider environment variables that start with "bref-ssm:"
         $envVarsToDecrypt = array_filter($envVars, function (string $value): bool {
@@ -130,4 +127,38 @@ private static function retrieveParametersFromSsm(?SsmClient $ssmClient, array $
 
         return $parameters;
     }
+
+    private static function getEnvironment(): ?string
+    {
+        if ($environment = getenv('BREF_ENV')){
+            return $environment;
+        }
+        return getenv('APP_ENV') ?: null;
+    }
+
+    private static function getEnvironmentPath(): ?string
+    {
+        if ($environment = getenv('BREF_ENV_PATH')){
+            return $environment;
+        }
+        return getenv('LAMBDA_TASK_ROOT') ?: getcwd();
+    }
+
+    private static function getEnvFile(): string
+    {
+        $env = self::getEnvironment();
+        $envFilePath = self::getEnvironmentPath()."/.env.{$env}";
+        return $env && file_exists($envFilePath) ? ".env.{$env}" : '.env';
+    }
+
+    private static function getEnvVars(): array
+    {
+        $env = getenv(null, true);
+        return array_merge(
+            is_array($env) ? $env : [],
+            Dotenv::createUnsafeImmutable(
+                self::getEnvironmentPath(),
+                self::getEnvFile()
+            )->safeLoad());
+    }
 }
diff --git a/tests/SecretsTest.php b/tests/SecretsTest.php
index 6792ace..aefdedf 100644
--- a/tests/SecretsTest.php
+++ b/tests/SecretsTest.php
@@ -11,11 +11,61 @@
 
 class SecretsTest extends TestCase
 {
+
+    const envToReset = [
+        'SOME_VARIABLE',
+        'SOME_OTHER_VARIABLE',
+        'APP_ENV',
+        'BREF_ENV',
+        'BREF_ENV_PATH',
+        'LAMBDA_TASK_ROOT'
+    ];
+
+    const envFilesToCleanup = [
+        '.env',
+        '.env.foobar'
+    ];
+
+    public static function tearDownAfterClass(): void
+    {
+        self::cleanupFiles();
+        parent::tearDownAfterClass();
+
+    }
+
     public function setUp(): void
+    {
+
+        self::cleanupFiles();
+
+        // reset env
+        array_map(function ($env) {
+            putenv($env);
+            unset($_ENV[$env], $_SERVER[$env]);
+        }, self::envToReset);
+    }
+
+    protected static function cleanupFiles()
     {
         if (file_exists(sys_get_temp_dir() . '/bref-ssm-parameters.php')) {
             unlink(sys_get_temp_dir() . '/bref-ssm-parameters.php');
         }
+
+        // cleanup dotenv files
+        array_map(function ($envFile){
+
+            if (file_exists(getcwd() .'/'. $envFile)) {
+                unlink(getcwd()  .'/'.  $envFile);
+            }
+
+            if (file_exists(__DIR__ . '/env/' . $envFile)) {
+                unlink(__DIR__ . '/env/' . $envFile);
+            }
+        }, self::envFilesToCleanup);
+
+        if(file_exists(__DIR__ . '/env')) {
+            rmdir(__DIR__ . '/env');
+        }
     }
 
     public function test decrypts env variables(): void
@@ -64,6 +114,80 @@ public function test throws a clear error message on missing permissions
         Secrets::loadSecretEnvironmentVariables($ssmClient);
     }
 
+    /**
+     * @testWith [null, null]
+     *           ["BREF_ENV_PATH", null]
+     *           ["LAMBDA_TASK_ROOT", null]
+     *           [null, "BREF_ENV"]
+     *           [null, "APP_ENV"]
+     *           ["BREF_ENV_PATH", "BREF_ENV"]
+     *           ["LAMBDA_TASK_ROOT", "APP_ENV"]
+     */
+    public function testLoadsSecretsFromDotenv(?string $envPath, ?string $envKey): void
+    {
+
+        if ($envPath) {
+            putenv("$envPath=" . __DIR__ . '/env');
+            mkdir( __DIR__ . '/env');
+        }
+        $envPath = $envPath ? __DIR__ . '/env' : getcwd();
+        copy(__DIR__ . '/fixtures/.env', "$envPath/.env");
+
+        if($envKey) {
+            putenv("$envKey=foobar");
+        }
+
+        putenv('SOME_VARIABLE');
+        putenv('SOME_OTHER_VARIABLE=helloworld');
+
+        // Sanity checks
+        $this->assertFalse(getenv('SOME_VARIABLE'));
+        $this->assertSame('helloworld', getenv('SOME_OTHER_VARIABLE'));
+
+        Secrets::loadSecretEnvironmentVariables($this->mockSsmClient());
+
+        $this->assertSame('foobar', getenv('SOME_VARIABLE'));
+        $this->assertSame('foobar', $_SERVER['SOME_VARIABLE']);
+        $this->assertSame('foobar', $_ENV['SOME_VARIABLE']);
+        // Check that the other variable was not modified
+        $this->assertSame('helloworld', getenv('SOME_OTHER_VARIABLE'));
+    }
+
+    /**
+     * @testWith [null, "BREF_ENV"]
+     *           [null, "APP_ENV"]
+     *           ["BREF_ENV_PATH", "BREF_ENV"]
+     *           ["BREF_ENV_PATH", "APP_ENV"]
+     *           ["LAMBDA_TASK_ROOT", "BREF_ENV"]
+     *           ["LAMBDA_TASK_ROOT", "APP_ENV"]
+     */
+    public function testLoadsSecretsFromDotenvForSpecificEnv(?string $envPath, string $envKey): void
+    {
+        if ($envPath) {
+            putenv("$envPath=" . __DIR__ . '/env');
+            mkdir( __DIR__ . '/env');
+        }
+
+        $envPath = $envPath ? __DIR__ . '/env' : getcwd();
+        copy(__DIR__ . '/fixtures/.env', "$envPath/.env.foobar");
+        putenv('SOME_VARIABLE');
+        putenv("$envKey=foobar");
+        putenv('SOME_OTHER_VARIABLE=helloworld');
+
+        // Sanity checks
+        $this->assertFalse(getenv('SOME_VARIABLE'));
+        $this->assertSame('foobar', getenv($envKey));
+        $this->assertSame('helloworld', getenv('SOME_OTHER_VARIABLE'));
+
+        Secrets::loadSecretEnvironmentVariables($this->mockSsmClient());
+
+        $this->assertSame('foobar', getenv('SOME_VARIABLE'));
+        $this->assertSame('foobar', $_SERVER['SOME_VARIABLE']);
+        $this->assertSame('foobar', $_ENV['SOME_VARIABLE']);
+        // Check that the other variable was not modified
+        $this->assertSame('helloworld', getenv('SOME_OTHER_VARIABLE'));
+    }
+
     private function mockSsmClient(): SsmClient
     {
         $ssmClient = $this->getMockBuilder(SsmClient::class)
diff --git a/tests/fixtures/.env b/tests/fixtures/.env
new file mode 100644
index 0000000..a4200e8
--- /dev/null
+++ b/tests/fixtures/.env
@@ -0,0 +1,2 @@
+SOME_VARIABLE=bref-ssm:/some/parameter
+SOME_OTHER_VARIABLE=i-should-not-overwrite-existing-value
\ No newline at end of file