diff --git a/src/Transformer/ColorModelTransformInterface.php b/src/Transformer/ColorModelTransformInterface.php
new file mode 100644
index 0000000..71fd556
--- /dev/null
+++ b/src/Transformer/ColorModelTransformInterface.php
@@ -0,0 +1,15 @@
+<?php
+
+
+namespace TorstenHettstedt\Colors\Transformer;
+
+
+use TorstenHettstedt\Colors\ColorModels\CyanMagentaYellowKey;
+use TorstenHettstedt\Colors\ColorModels\RedGreenBlue;
+
+interface ColorModelTransformInterface
+{
+    public function toRedGreenBlue(): RedGreenBlue;
+
+    public function toCyanMagentaYellowKey(): CyanMagentaYellowKey;
+}
\ No newline at end of file
diff --git a/src/Transformer/CyanMagentaYellowKeyTransformer.php b/src/Transformer/CyanMagentaYellowKeyTransformer.php
new file mode 100644
index 0000000..8da4437
--- /dev/null
+++ b/src/Transformer/CyanMagentaYellowKeyTransformer.php
@@ -0,0 +1,33 @@
+<?php
+
+
+namespace TorstenHettstedt\Colors\Transformer;
+
+
+use TorstenHettstedt\Colors\ColorModels\CyanMagentaYellowKey;
+use TorstenHettstedt\Colors\ColorModels\RedGreenBlue;
+
+class CyanMagentaYellowKeyTransformer implements ColorModelTransformInterface
+{
+
+    protected CyanMagentaYellowKey $color;
+
+    /**
+     * @param CyanMagentaYellowKey $color
+     */
+    public function __construct(CyanMagentaYellowKey $color)
+    {
+        $this->color = $color;
+    }
+
+
+    public function toRedGreenBlue(): RedGreenBlue
+    {
+        // TODO: Implement toRedGreenBlue() method.
+    }
+
+    public function toCyanMagentaYellowKey(): CyanMagentaYellowKey
+    {
+        // TODO: Implement toCyanMagentaYellowKey() method.
+    }
+}
\ No newline at end of file
diff --git a/tests/unit/Transformer/CyanMagentaYellowKeyTransformerTest.php b/tests/unit/Transformer/CyanMagentaYellowKeyTransformerTest.php
new file mode 100644
index 0000000..70b55ab
--- /dev/null
+++ b/tests/unit/Transformer/CyanMagentaYellowKeyTransformerTest.php
@@ -0,0 +1,133 @@
+<?php /** @noinspection PhpArrayShapeAttributeCanBeAddedInspection */
+
+namespace TorstenHettstedtUnitTests\Colors\Transformer;
+
+use Codeception\Test\Unit;
+use Exception;
+use TorstenHettstedt\Colors\ColorModels\CyanMagentaYellowKey;
+use TorstenHettstedt\Colors\Transformer\CyanMagentaYellowKeyTransformer;
+
+class CyanMagentaYellowKeyTransformerTest extends Unit
+{
+
+    protected CyanMagentaYellowKey $color;
+
+    /**
+     * @return float[][][]
+     */
+    public function validRgbValuesProvider(): array
+    {
+        return [
+            'weiß' => [
+                [
+                    'cyan'    => 0.0,
+                    'magenta' => 0.0,
+                    'yellow'  => 0.0,
+                    'key'     => 0.0,
+                ],
+                [
+                    'red'   => 1.0,
+                    'green' => 1.0,
+                    'blue'  => 1.0,
+                ]
+            ],
+            'schwarz' => [
+                [
+                    'cyan'    => 0.0,
+                    'magenta' => 0.0,
+                    'yellow'  => 0.0,
+                    'key'     => 1.0,
+                ],
+                [
+                    'red'   => 0.0,
+                    'green' => 0.0,
+                    'blue'  => 0.0,
+                ]
+            ],
+            'cyan' => [
+                [
+                    'cyan'    => 1.0,
+                    'magenta' => 0.0,
+                    'yellow'  => 0.0,
+                    'key'     => 0.0,
+                ],
+                [
+                    'red'   => 0.0,
+                    'green' => 1.0,
+                    'blue'  => 1.0,
+                ]
+            ],
+            'magenta' => [
+                [
+                    'cyan'    => 0.0,
+                    'magenta' => 1.0,
+                    'yellow'  => 0.0,
+                    'key'     => 0.0,
+                ],
+                [
+                    'red'   => 1.0,
+                    'green' => 0.0,
+                    'blue'  => 1.0,
+                ]
+            ],
+            'gelb' => [
+                [
+                    'cyan'    => 0.0,
+                    'magenta' => 0.0,
+                    'yellow'  => 1.0,
+                    'key'     => 0.0,
+                ],
+                [
+                    'red'   => 1.0,
+                    'green' => 1.0,
+                    'blue'  => 0.0,
+                ]
+            ],
+        ];
+    }
+
+    /**
+     * @param array $cmyk
+     * @param array $rgb
+     *
+     * @dataProvider validRgbValuesProvider
+     *
+     * @throws Exception
+     */
+    public function testToRedGreenBlue(array $cmyk, array $rgb)
+    {
+        $this->color = $this->make(CyanMagentaYellowKey::class, $cmyk);
+
+        $transformer = new CyanMagentaYellowKeyTransformer($this->color);
+
+        $color = $transformer->toRedGreenBlue();
+
+        $this->assertEquals($rgb['red'], $color->getRed());
+        $this->assertEquals($rgb['green'], $color->getGreen());
+        $this->assertEquals($rgb['blue'], $color->getBlue());
+
+    }
+
+    /**
+     * @param array $cmyk
+     * @param array $rgb
+     *
+     * @dataProvider validRgbValuesProvider
+     *
+     * @throws Exception
+     */
+    public function testToCyanMagentaYellowKey(array $cmyk, array $rgb)
+    {
+
+        $this->color = $this->make(CyanMagentaYellowKey::class, $cmyk);
+
+        $transformer = new CyanMagentaYellowKeyTransformer($this->color);
+
+        $color = $transformer->toCyanMagentaYellowKey();
+
+        $this->assertEquals($rgb['cyan'], $color->getCyan());
+        $this->assertEquals($rgb['magenta'], $color->getMagenta());
+        $this->assertEquals($rgb['yellow'], $color->getYellow());
+        $this->assertEquals($rgb['key'], $color->getKey());
+    }
+}