diff --git a/README.md b/README.md
index bfc9c55..f41bf9e 100644
--- a/README.md
+++ b/README.md
@@ -152,6 +152,7 @@ tempering simulations, JCTC 3(1):26-41*
 
 TODO
 ---
+- Option to output histograms
 - Replica exchange
 
 License & Citing