Hello, I think we should provide a zope.testing package which does not emit deprecation warnings while running the testrunner on other packages, otherwise there is no way to really understand why the package you are working on is using a deprecated API. I propose the patch attached to this message to zope.testing. It tries to avoid importing zope.testing.doctest unless it is really needed. In this way, developers can see the DeprecationWarning with the path of *their* code, and fix it, instead of receiving the DeprecationWarning because the testrunner imports zope.testing.doctest itself. Before applying the patch, running the tests on another package produced this output: ----------------------------------------------------------------------- .../zope/testing/testrunner/debug.py:23: DeprecationWarning: zope.testing.doctest is deprecated in favour of the Python standard library doctest module from zope.testing import doctest Running zope.testing.testrunner.layer.UnitTests tests: ... ----------------------------------------------------------------------- After applying my patch, I get this: ----------------------------------------------------------------------- .../zope/interface/tests/test_adapter.py:405: DeprecationWarning: zope.testing.doctest is deprecated in favour of the Python standard library doctest module from zope.testing import doctest Running zope.testing.testrunner.layer.UnitTests tests: ... ----------------------------------------------------------------------- Comments? Thanks, Fabio