Purpose Minimally invasive surgery has been shown to decrease postoperative morbidity and length of stay for a number of surgical procedures. Furthermore, length of stay after open radical prostatectomy has decreased dramatically during the last decade. We examined differences in length of stay between a prospectively evaluated cohort of patients who underwent radical retropubic prostatectomy and robot assisted laparoscopic prostatectomy. Materials and Methods Between January 2003 and March 2006, 1,003 radical prostatectomies were performed at our hospital. Data were collected in prospective fashion and a comparison was made between 374 patients who underwent radical retropubic prostatectomy and 629 who underwent robot assisted laparoscopic prostatectomy. Length of stay, factors influencing length of stay, readmission rates and unscheduled clinic or emergency room visits were evaluated. Patients in the 2 groups were treated using the same clinical care pathway. Results Overall 94.3% of patients in the radical retropubic prostatectomy group and 97.5% in the robot assisted laparoscopic prostatectomy group were discharged home on or before postoperative day 1. Mean length of stay in the radical retropubic and robot assisted laparoscopic prostatectomy groups was 1.25 (median 1.09) and 1.17 days (median 1.03), which was similar and not statistically different (p = 0.27). Readmission rates were similar in robot assisted laparoscopic and radical retropubic prostatectomy patients (7% and 5%, respectively, p = 0.12). Unscheduled clinic or emergency room visits were the same in the robot assisted laparoscopic and radical retropubic prostatectomy groups (10%, p = 0.95). Conclusions Patients who underwent radical retropubic prostatectomy or robot assisted laparoscopic prostatectomy can be treated on the same clinical pathway. A targeted hospital discharge date of postoperative day 1 can be achieved in the majority of patients who underwent radical prostatectomy. Readmission rates or unscheduled hospital visits are necessary in a small percent of patients treated with an early discharge program, of which the majority are caused by ileus.