We are pleased to publish, soon after its delivery, the 1998 Emanuel Miller lecture by Michael Rutter on the subject of autism, a masterly review of the history of clinical practice in this condition and the way in which it has both informed and been informed by research. It is now 55 years since Kanner's seminal paper, and that is over half a century of controversy which shows no signs of abating in intensity, although perhaps the focus is changing. Nowhere is this more clearly evident than in the field of clinical practice. As Rutter's review article brings out, empirical research findings have been crucial in bringing about such change. Nevertheless, he emphasises that the traffic has been far from one-way. Many research advances were prompted by astute clinical observations and some extravagant research claims were given a more balanced perspective by being viewed in the light of clinical experience. Progress takes place through a series of fits and starts, and the two-way interplay between research and clinical practice is essential to ensure that the gains are real, rather than misleading. We are still a very long way from having an effective means of preventing or treating autism but the lessons of the past provide a useful guide on how best to move ahead in the future.