diff --git a/src/de/dhbwstuttgart/typeinference/unify/Unifier.java b/src/de/dhbwstuttgart/typeinference/unify/Unifier.java
new file mode 100644
index 00000000..acc14281
--- /dev/null
+++ b/src/de/dhbwstuttgart/typeinference/unify/Unifier.java
@@ -0,0 +1,11 @@
+package de.dhbwstuttgart.typeinference.unify;
+
+import java.util.Set;
+
+import de.dhbwstuttgart.typeinference.Pair;
+
+public interface Unifier {
+
+    public Set<Set<Pair>> apply (Set<Pair> E);
+
+}