diff --git a/gw_requirements.txt b/gw_requirements.txt
index 9181f570314f79af35ce4c3fdbfc6ffdeec8cd48..03cdd7e5739c6ca15d37dc7ac2be24ca964c6e7b 100644
--- a/gw_requirements.txt
+++ b/gw_requirements.txt
@@ -3,3 +3,4 @@ lalsuite
 gwpy
 tables
 pyfftw
+scikit-learn