diff --git a/README.rst b/README.rst
--- a/README.rst
+++ b/README.rst
@@ -23,7 +23,8 @@ Kallithea was forked from RhodeCode in J
 
 Installation
 ------------
-Official releases of Kallithea can be installed via::
+Kallithea requires Python_ 2.x and it is recommended to install it in a
+virtualenv_. Official releases of Kallithea can be installed with::
 
     pip install kallithea