Abstract
The concept of monitoring neuroleptic drugs by means of chemical or pharmacological assays is considered from a historical and strategic point of view. The objectives of compliance control, reduction of long-term exposure, titration to a therapeutic range, and solution of medicolegal problems are separately considered. The relative merits of chemically specific (mainly chromatographic) and clinically specific (radioreceptor) assays are considered. An algorithm for interpretation of a neuroleptic concentration measurement is presented.