diff --git a/docs/install.rst b/docs/install.rst
index c63b254..621b103 100644
--- a/docs/install.rst
+++ b/docs/install.rst
@@ -16,6 +16,7 @@ Requirements
 - Python 2.7, 3.2+ or pypy (including the development headers)
 - Libgit2 v0.21.1+
 - cffi 0.8.1+
+- Libssh2, optional, used for SSH network operations.
 
 .. warning::