diff --git a/Tools/setup/OSX.sh b/Tools/setup/OSX.sh
index 2ccbe700d0..ddd8edba82 100755
--- a/Tools/setup/OSX.sh
+++ b/Tools/setup/OSX.sh
@@ -3,12 +3,41 @@
 # script directory
 DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
 
-brew tap PX4/px4
-brew install px4-dev
+# Reinstall if --reinstall set
+REINSTALL_FORMULAS=""
+# Install simulation tools?
+INSTALL_SIM=""
 
-# python dependencies
+# Parse arguments
+for arg in "$@"
+do
+  if [[ $arg == "--reinstall" ]]; then
+    REINSTALL_FORMULAS=$arg
+  elif [[ $arg == "--sim-tools" ]]; then
+    INSTALL_SIM=$arg
+  fi
+done
+
+# Install px4-dev formula
+brew tap PX4/px4
+if [ brew ls --versions px4-dev > /dev/null ]; then
+  brew install px4-dev
+elif [[ $REINSTALL_FORMULAS == "--reinstall" ]]; then
+  brew reinstall px4-dev
+fi
+
+# Python dependencies
 sudo easy_install pip
-sudo -H pip install -r ${DIR}/requirements.txt
+sudo -H pip install --upgrade --force-reinstall pip
+sudo -H pip install -I -r ${DIR}/requirements.txt
 
 # Optional, but recommended additional simulation tools:
-brew install px4-sim
+if [[ $INSTALL_SIM == "--sim-tools" ]]; then
+  if [ brew ls --versions px4-sim > /dev/null ]; then
+    brew install px4-sim
+  elif [[ $REINSTALL_FORMULAS == "--reinstall" ]]; then
+    brew reinstall px4-sim
+  fi
+fi
+
+echo "All set! PX4 toolchain installed!"