I have looked for an easy way to install/compile Numpy with OpenBLAS but didn't find an easy answer. All the documentation I have seen takes too much knowledge as granted for someone like me who is not used to compile software. There are two packages in Ubuntu related to OpenBLAS : libopenblas-base and libopenblas-dev. Once they are installed, what should I do to install Numpy again with them? Thanks! Note that when these OpenBLAS packages are installed, Numpy doesn't work anymore: it can't be imported: ImportError: /usr/lib/liblapack.so.3gf: undefined symbol: ATL_chemv. This was noticed here already. Answer to the question: Run sudo update-alternatives --all and set liblapack.so.3gf to /usr/lib/lapack/liblapack.so.3gf