For patients who gain a troublesome amount of weight on antipsychotics, switching to a less obesogenic agent is an option. Aripiprazole appears to cause less weight gain than many other antipsychotics. We report on changes in weight, and other risk factors for heart disease, in thirty-three schizophrenia patients who agreed to switch from other antipsychotics to aripiprazole in an open, flexible-dose, eight-week trial. All patients were successfully switched. There were no significant changes in PANSS symptom scores or in CGI. Weight (Wt), waist circumference (WC), and low-density lipoprotein (LDL) decreased significantly in the group as a whole. In patients switched from olanzapine to aripiprazole, Wt, WC, LDL, fasting glucose, and triglycerides were significantly decreased as compared to baseline. Substantial decreases in several risk factors were also seen in patients switched from quetiapine, but these changes did not reach statistical significance.