diff --git a/requirements.txt b/requirements.txt
index efc5b1b48ba73f9655383903b6163b756afb43a8..05052114aa3b62359d89310cb74a649efd411e5f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,7 @@
 six==1.*
 deprecation==1.*
 numpy==1.*
+scipy>=0.18,<1
 nibabel==2.*
 indexed_gzip>=0.6.1,<1
 wxPython>=3.0.2.0,<4.1