diff --git a/src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidator.java b/src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidator.java
index 3afeb84..a037ad0 100644
--- a/src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidator.java
+++ b/src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidator.java
@@ -12,7 +12,7 @@ public class PersonGroupValidator implements Validator<Person> {
 
 	@Override
 	public ValidationResult apply(Person value, ValueContext context) {
-		if (value.hasAnyGroup()) {
+		if (!value.hasAnyGroup()) {
 			return ValidationResult.error("Es müssen Gruppen gesetzt sein!");
 		}
 
diff --git a/src/test/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidatorTest.java b/src/test/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidatorTest.java
index 5948273..5cf313e 100644
--- a/src/test/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidatorTest.java
+++ b/src/test/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/PersonGroupValidatorTest.java
@@ -26,7 +26,7 @@ class PersonGroupValidatorTest {
 	@Test
 	void testError() {
 		ValidationResult result = validator.apply(person, null);
-		assertTrue(result.isError());
+		assertTrue("Error expected on empty groups", result.isError());
 	}
 
 	@Test