Recommendation ITU-T P.808 describes a crowdsourcing approach for conducting subjective evaluations of speech quality. In comparison to laboratory tests, tests using a crowdsourcing approach rely on participants that are connected via an online platform, and whose task is to evaluate speech quality in their own environments, using their own devices. This Recommendation gives guidance on the test material, experimental design, and the procedure for conducting listening tests in the crowd. The methods are to be seen as complementary to laboratory-based evaluations which are described in ITU-T P.800 and ITU T P.835.