diff --git a/doc/INSTALL.md b/doc/INSTALL.md
index bec63e75d..836785eb2 100644
--- a/doc/INSTALL.md
+++ b/doc/INSTALL.md
@@ -264,6 +264,7 @@ Configure Python 3.x & get mako:
 
 Build lightning:
 
+    $ pip install -r requirements.txt
     $ ./configure
     $ make