I develop for both Python 2 and Python 3 on OS X and my setup is pretty similar to rgacote's. I installed both versions of Python using homebrew[0] so it doesn

I develop for both Python 2 and Python 3 on OS X and my setup is pretty similar to rgacote's. I installed both versions of Python using homebrew[0] so it doesn't matter which version OS X ships with. Python 2 is still the default. So I have python and pip, and then python3 and pip3. Every project I work on has a virtual environment[1], which is named after the owner and the project, e.g. citruspi-skynet. If it's a Python 2 project, I just create the virtual environment normally. mkvirtualenv citruspi-skynet If it's a Python 3 project, I set the location of Python interpreter. mkvirtualenv -p $(which python3) citruspi-skynet I've run into situations where I have to port a Python 2 project to Python 3, while maintaining the Python 2 project. In that case, I normally use the same repository, but a new branch. However, I'll keep two copies of the repository locally so I can work on both branches at the same time. Code/ citruspi/ skynet skynet3 And then I'll have two virtual environments, citruspi-skynet and citruspi-skynet3. I haven't run into any issues with this setup and I've been pretty happy. [0]: http://brew.sh http://brew.sh [1]: https://virtualenv.pypa.io/en/latest/ https://virtualenv.pypa.io/en/latest/