The evidence presented in this review supports a post-vasectomy testing protocol with only one test (showing azoospermia) at three months post-vasectomy and after a minimum of 20 ejaculations. If the sample is positive at three months, then periodic testing can continue until azoospermia is reached. In patients who do not reach azoospermia after prolonged testing, cautious assurance of success could be given provided only low levels of non-motile sperm are present. No evidence was found to support a recommendation of histological testing of the excised vas deferens. The proposed protocol could considerably reduce costs of post-vasectomy testing.