There has been a longstanding concern over the cardiovascular effects of antidepressant medication, originally prompted by the observation that patients who take overdoses of tricyclics most frequently die a cardiac death. This article (1) reviews the data on the cardiovascular effects of tricyclics, highlighting the methodological problems that plagued the early studies; (2) presents current techniques that are used in cardiovascular studies of psychotropic medication; and (3) discusses the problems of studying new nontricyclic drugs. Further, the article discusses some aspects of the complicated relationship between brain and heart function that are specifically relevant to whether there is inherent reason to believe that any drug that is effective as an antidepressant will necessarily affect cardiac function.