diff --git a/CHANGELOG.md b/CHANGELOG.md
index c398e07..945d128 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,8 +18,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Implement `Atomic<u64>` for `AtomicU64` for gauges.
   See [PR 226].
 
-[PR 226]: https://github.com/prometheus/client_rust/pull/198
+- Implement `EnableLabelValue` for `bool`.
+  See [PR 237]
+
+[PR 173]: https://github.com/prometheus/client_rust/pull/173
 [PR 198]: https://github.com/prometheus/client_rust/pull/198
+[PR 226]: https://github.com/prometheus/client_rust/pull/226
+[PR 237]: https://github.com/prometheus/client_rust/pull/237
 
 ### Added
 
diff --git a/src/encoding.rs b/src/encoding.rs
index 6f3f2ef..9e2acac 100644
--- a/src/encoding.rs
+++ b/src/encoding.rs
@@ -537,6 +537,12 @@ where
     }
 }
 
+impl EncodeLabelValue for bool {
+    fn encode(&self, encoder: &mut LabelValueEncoder) -> Result<(), std::fmt::Error> {
+        encoder.write_str(if *self { "true" } else { "false" })
+    }
+}
+
 macro_rules! impl_encode_label_value_for_integer {
     ($($t:ident),*) => {$(
         impl EncodeLabelValue for $t {