diff --git a/requirements.txt b/requirements.txt
index d54bb8958a..c87fa25d27 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,10 +1,11 @@
-colorama
-PrettyTable
-pyserial
-IntelHex
+colorama>=0.3.3
+PySerial>=2.7
+PrettyTable>=0.7.2
+Jinja2>=2.7.3
+IntelHex>=1.3
+project-generator>=0.9.3,<0.10.0
+junit-xml
+pyYAML
+requests
 mbed-ls
 mbed-greentea
-project-generator>=0.9.3,<0.10.0
-Jinja2
-junit-xml
-requests