In recent years, with the notable exception of clinical research in developing countries, there has been considerable progress in minimizing the risk of exploitation due to inappropriate inclusion in clinical trials. In part, this is due to the fact that no one seriously disputes the claim that it is wrong to exploit others. Regrettably, there has not been similar progress with respect to the problem of inappropriate exclusion from trial participation. In part, this is because many firmly believe (on beneficient or paternalistic grounds) that it is wrong to include certain classes of persons in clinical trials and thereby to expose them to the potential harms of trial participation. This entrenched belief explains, in part, why the argument for appropriate inclusion in clinical trials has had to be repeated time and again for different classes of persons, be they children, women or pregnant women