diff --git a/requirements.txt b/requirements.txt
index 24ce15a..321875f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1 +1,2 @@
-numpy
+numpy<1.12 ; python_version >= '3.2' and python_version < '3.4' # numpy starting from 1.12 doesn't support python 3.2 and 3.3
+numpy ; python_version < '3.0' or python_version >= '3.4' # newest numpy for python 2.7, 3.4 and higher
\ No newline at end of file