Measured by any criteria, research in chronobiology in general and chronopharmacology in particular has expanded rapidly in recent years. This expansion has been paralleled by an increasing recognition by those outside the field of the relevance and significance of recent developments in chronobiology. Advances in two areas have been chiefly responsible. First, application of the full range of modern techniques in behavioral, neurochemical, and molecular biology have greatly improved our understanding of basic clock mechanisms. In several species the genetic basis of the circadian clock is...