pyeee is a Python library for performing parameter screening of computational models. It uses Efficient or Sequential Elementary Effects, an extension of Morris' method of Elementary Effects, published by Cuntz M, Mai J et al. (2015) Computationally inexpensive identification of noninformative model parameters by sequential screening, Water Resources Research 51, 6417-6441, doi: 10.1002/2015WR016907. pyeee can be used with Python functions as well as external executables using libraries such as partialwrap. Function evaluations can be distributed with Python's multiprocessing or via the Message Passing Interface (MPI).