diff --git a/src/interpreter/value/mod.rs b/src/interpreter/value/mod.rs
index 840ac1d..43d5226 100644
--- a/src/interpreter/value/mod.rs
+++ b/src/interpreter/value/mod.rs
@@ -1,7 +1,9 @@
 mod function;
+mod pair;
 mod string;
 
 pub use function::Function;
+pub use pair::DotPair;
 pub use string::Str;
 
 use std::{collections::BTreeMap, rc::Rc};
@@ -10,7 +12,7 @@ pub type OrderedF64 = ordered_float::OrderedFloat<f64>;
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum Value<'s> {
-    List(/* TODO: List impl (or dotted pair) */),
+    DotPair(Rc<DotPair<'s>>),
     Vector(Rc<Vec<Self>>),
     Map(Rc<BTreeMap<Self, Self>>),
     Symbol(Str<'s>),
@@ -19,4 +21,5 @@ pub enum Value<'s> {
     String(Str<'s>),
     Function(Function),
     Macro(Function),
+    Nil,
 }
diff --git a/src/interpreter/value/pair.rs b/src/interpreter/value/pair.rs
new file mode 100644
index 0000000..6923cc7
--- /dev/null
+++ b/src/interpreter/value/pair.rs
@@ -0,0 +1,4 @@
+use super::Value;
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DotPair<'s>(pub Value<'s>, pub Value<'s>);