The Sherrington School of Physiology at St. Thomas' Hospital provided a natural venue for four days of enthusiastic debate on Sherrington's Final Common Path -the alpha motoneurone and related matters; Sherrington himself held a lecturership at St. Thomas' just over a century ago. The occasion was a happy one. Most participants already knew each other, the topics were familiar, the discussion was vigorous and critical but without personal rancor. The program had set out to encourage debate with 'critiques' both of the oral papers and the posters; their inclusion in the present volume helps to show where we are standing on rock rather than sand. In spite of a venerable history some surprisingly simple matters remain controversial, such as the information content of the signals from the Golgi tendon organs. To those working on alpha and gamma motoneurones and their control this volume provides an essential up-dating. Classical problems continue to be attacked on a broad front; advance is steady and continuous, a swelling tide rather than a sudden view of the summit. But in some sectors the difficulties are so great that to the outsider little might seem to change, the same battles continuing; but even here, the terms of debate change and concensus develops. Other branches of biology claim breakthrough upon breakthrough from the routine application of the new technologies, so we have to be the first to ask whether our classical approach to science can still be justified.