diff --git a/src/JsonSchema/PhpBuilder.php b/src/JsonSchema/PhpBuilder.php
index 8401a29..cebdfcf 100644
--- a/src/JsonSchema/PhpBuilder.php
+++ b/src/JsonSchema/PhpBuilder.php
@@ -19,6 +19,7 @@
 use Swaggest\PhpCodeBuilder\PhpFlags;
 use Swaggest\PhpCodeBuilder\PhpFunction;
 use Swaggest\PhpCodeBuilder\PhpNamedVar;
+use Swaggest\PhpCodeBuilder\PhpStdType;
 use Swaggest\PhpCodeBuilder\Property\AdditionalPropertiesGetter;
 use Swaggest\PhpCodeBuilder\Property\AdditionalPropertySetter;
 use Swaggest\PhpCodeBuilder\Property\Getter;
@@ -73,6 +74,13 @@ public function __construct()
      */
     public $declarePropertyDefaults = false;
 
+    /**
+     * Build setter and getter methods for additional properties
+     * on a boolean true value for `additionalProperties`.
+     * @var bool
+     */
+    public $buildAdditionalPropertyMethodsOnTrue = false;
+
     /**
      * @param SchemaContract $schema
      * @param string $path
@@ -210,9 +218,19 @@ private function makeClass($schema, $path)
             }
         }
 
+        $additionalPropertiesType = null;
+        $buildAdditionalPropertiesMethods = false;
         if ($schema->additionalProperties instanceof Schema) {
-            $class->addMethod(new AdditionalPropertiesGetter($this->getType($schema->additionalProperties)));
-            $class->addMethod(new AdditionalPropertySetter($this->getType($schema->additionalProperties)));
+            $additionalPropertiesType = $this->getType($schema->additionalProperties);
+            $buildAdditionalPropertiesMethods = true;
+        } elseif ($this->buildAdditionalPropertyMethodsOnTrue && $schema->additionalProperties === true) {
+            $additionalPropertiesType = PhpStdType::mixed();
+            $buildAdditionalPropertiesMethods = true;
+        }
+
+        if ($buildAdditionalPropertiesMethods) {
+            $class->addMethod(new AdditionalPropertiesGetter($additionalPropertiesType));
+            $class->addMethod(new AdditionalPropertySetter($additionalPropertiesType));
         }
 
         if ($schema->patternProperties !== null) {
diff --git a/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-new-behavior.txt b/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-new-behavior.txt
new file mode 100644
index 0000000..2463ab7
--- /dev/null
+++ b/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-new-behavior.txt
@@ -0,0 +1,47 @@
+/**
+ * @method static mixed import($data, Swaggest\JsonSchema\Context $options = null)
+ */
+class Root extends Swaggest\JsonSchema\Structure\ClassStructure
+{
+    /**
+     * @param Swaggest\JsonSchema\Constraint\Properties|static $properties
+     * @param Swaggest\JsonSchema\Schema $ownerSchema
+     */
+    public static function setUpProperties($properties, Swaggest\JsonSchema\Schema $ownerSchema)
+    {
+        $ownerSchema->type = Swaggest\JsonSchema\Schema::OBJECT;
+        $ownerSchema->additionalProperties = true;
+    }
+
+    /**
+     * @return array
+     * @codeCoverageIgnoreStart
+     */
+    public function getAdditionalPropertyValues()
+    {
+        $result = array();
+        if (!$names = $this->getAdditionalPropertyNames()) {
+            return $result;
+        }
+        foreach ($names as $name) {
+            $result[$name] = $this->$name;
+        }
+        return $result;
+    }
+    /** @codeCoverageIgnoreEnd */
+
+    /**
+     * @param string $name
+     * @param mixed $value
+     * @return self
+     * @codeCoverageIgnoreStart
+     */
+    public function setAdditionalPropertyValue($name, $value)
+    {
+        $this->addAdditionalPropertyName($name);
+        $this->{$name} = $value;
+        return $this;
+    }
+    /** @codeCoverageIgnoreEnd */
+}
+
diff --git a/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-old-behavior.txt b/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-old-behavior.txt
new file mode 100644
index 0000000..2bede1c
--- /dev/null
+++ b/tests/resources/JsonSchema/AdvancedTest/testBuildingAdditionalPropertyMethodsOnTrue-old-behavior.txt
@@ -0,0 +1,16 @@
+/**
+ * @method static mixed import($data, Swaggest\JsonSchema\Context $options = null)
+ */
+class Root extends Swaggest\JsonSchema\Structure\ClassStructure
+{
+    /**
+     * @param Swaggest\JsonSchema\Constraint\Properties|static $properties
+     * @param Swaggest\JsonSchema\Schema $ownerSchema
+     */
+    public static function setUpProperties($properties, Swaggest\JsonSchema\Schema $ownerSchema)
+    {
+        $ownerSchema->type = Swaggest\JsonSchema\Schema::OBJECT;
+        $ownerSchema->additionalProperties = true;
+    }
+}
+
diff --git a/tests/src/PHPUnit/JsonSchema/AdvancedTest.php b/tests/src/PHPUnit/JsonSchema/AdvancedTest.php
index e8142a0..e0d4fb9 100644
--- a/tests/src/PHPUnit/JsonSchema/AdvancedTest.php
+++ b/tests/src/PHPUnit/JsonSchema/AdvancedTest.php
@@ -733,4 +733,43 @@ public function testClassPropertyDefaultsDeactivated()
         $this->assertContains($expected, $result);
     }
 
+    public function testBuildingAdditionalPropertyMethodsOnTrue()
+    {
+        $schemaData = json_decode(<<<'JSON'
+{
+  "type": "object",
+  "additionalProperties": true
+}
+JSON
+        );
+
+        // Keeping the old behavior
+        $schema = Schema::import($schemaData);
+        $builder = new PhpBuilder();
+        $class = $builder->getClass($schema, 'Root');
+
+        $result = '';
+        foreach ($builder->getGeneratedClasses() as $class) {
+            $result .= $class->class . "\n\n";
+        }
+
+        $expected = file_get_contents(__DIR__ . '/../../../resources/JsonSchema/AdvancedTest/' . __FUNCTION__ . '-old-behavior.txt');
+
+        $this->assertSame($expected, $result, 'Getter and setter not created (old behavior - flag: false)');
+
+        // Testing the new behavior with setted flag
+        $schema = Schema::import($schemaData);
+        $builder = new PhpBuilder();
+        $builder->buildAdditionalPropertyMethodsOnTrue = true;
+        $class = $builder->getClass($schema, 'Root');
+
+        $result = '';
+        foreach ($builder->getGeneratedClasses() as $class) {
+            $result .= $class->class . "\n\n";
+        }
+
+        $expected = file_get_contents(__DIR__ . '/../../../resources/JsonSchema/AdvancedTest/' . __FUNCTION__ . '-new-behavior.txt');
+
+        $this->assertSame($expected, $result, 'Getter and setter created (new behavior - flag: true)');
+    }
 }
\ No newline at end of file