diff --git a/exercises/sublist/src/lib.rs b/exercises/sublist/src/lib.rs
index 8b1378917..b41f4375d 100644
--- a/exercises/sublist/src/lib.rs
+++ b/exercises/sublist/src/lib.rs
@@ -1 +1,11 @@
+#[derive(Debug, PartialEq)]
+pub enum Comparison {
+    Equal,
+    Sublist,
+    Superlist,
+    Unequal,
+}
 
+pub fn sublist<T: PartialEq>(_first_list: &[T], _second_list: &[T]) -> Comparison {
+    unimplemented!("Determine if the first list is equal to, sublist of, superlist of or unequal to the second list.");
+}