We have described how the pharmacology of agents that act on the central nervous system (CNS) and endocrine system were incorporated into a case-based, multidisciplinary, integrated sophomore medical curriculum at Southern Illinois University School of Medicine (SIUSM). Faculty members from the Departments of Pharmacology, Pathology, Internal Medicine, Psychiatry, and Neurology were major participants in the CNS block, and faculty with primary expertise in radiology, epidemiology, and immunology also participated. Integrated sessions involving the entire class were organized around brief patient cases, which were given to the students in advance of the session. During the sessions, each patient case was presented by a physician or pathologist who briefly described symptoms, history, physical findings, differential diagnosis, and the classification of the subtypes of the particular class of disorder. The pathophysiology of the disease was discussed, and the pharmacology of agents to be considered for therapy was presented in the context of the Pharmacology Mental Algorithm, a systematic and rational approach to drug therapy. The session was completed by a clinician who added further clinically relevant information, which was followed by a question-and-answer period involving all faculty participants. The CNS block was presented over a 1-month period and included standardized patients and real patients who consistently exhibited specific disease findings, and these patient-oriented sessions were followed with small group tutorial sessions. Single discipline large-group sessions were also used to present material that is introductory or unique to a particular discipline. Student knowledge was assessed, using integrated evaluations based on case vignettes with multiple-choice questions provided by each discipline. The goal of the examination was to evaluate knowledge base in the discipline areas and its application to clinical problem-solving. A practical evaluation of each student's patient examination skills in CNS was also performed by clinicians. Feedback from the students on the organ system activities was obtained using a questionnaire. Development of these sessions required leadership and a considerable amount of time to organize, improve, and update sessions. The integrated approach largely eliminated the use of conflicting terminology and redundancy of material common with separate presentations on the same subject by different disciplines. The multidisciplinary, case-based sessions were perceived to be instructive, valuable learning experiences, based on formal and informal student and faculty feedback.