Another alternative - I would often prefer just doing what metafunc.addcall does if you don't specify an id, which is just make an integer, like so: <Function 'test_filterPrecipOrTS[0]'> <Function 'test_filterPrecipOrTS[1]'> <Function 'test_filterPrecipOrTS[2]'> <Function 'test_filterPrecipOrTS[3]'> <Function 'test_filterPrecipOrTS[4]'> <Function 'test_filterPrecipOrTS[5]'> Maybe it is wrong and should be updated to use idmaker :P But basically, if the id can't be simple and meaningful to me (and with parametrize it is often not), an integer would be less "visual noise" and in the case of the mark parametrize, easy to map back to the specific test data in the case of a failure. Brianna -- They've just been waiting in a mountain for the right moment: http://modernthings.org/