Psychosocial factors substance abuse, noncompliance, psychiatric problems, and obesity in relation to the outcome of heart transplantation have been investigated. Data were gathered at the time of initial assessment, and patients (n = 53) were monitored during the follow-up after heart transplantation (mean 18 months). Noncompliance, psychiatric problems, or excessive weight before heart transplantation continued after heart transplantation. Significantly fewer substance abusers exhibited similar behavior after heart transplantation (p < 0.01), although in many cases this exposed other psychiatric or compliance problems. Patients with psychiatric problems after heart transplantation had a higher risk of infection (p < 0.01). Both these patients and those who were noncompliant had higher incidences of hospital readmission (p < 0.01) which were reflected in higher medical costs (p < 0.01) during the second year after heart transplantation in both subgroups. We conclude that (1) heart transplant recipients do not alter previous behavior after heart transplantation except with regard to substance abuse, (2) patients exhibiting substance abuse before heart transplantation and abstaining after heart transplantation have other psychosocial problems, (3) psychosocial problems after heart transplantation do not increase the risk for medical complications in the early posttransplantation period except with regard to infection, and (4) the presence of noncompliance and psychiatric problems after heart transplantation is related to increased readmissions and higher total medical costs.