OBJECTIVE: to compare the comprehension gained by standard consent (SC) vs a unique interactive multimedia presentation (IMP), for radical prostatectomy (RP), as informed consent for RP requires that the patient understands the procedure and potential complications. PATIENTS AND METHODS: forty patients undergoing RP were prospectively randomized to SC or IMP, followed by a 26-question test on critical aspects of the surgery and its implications. The groups were crossed over and re-tested, with a subsequent statistical analysis. SC involved typical verbal interaction and consultation with physicians and nurses, whilst the IMP provided consistent and animated information on these topics, and included multiple-choice questions probing understanding of key points. Progression through the IMP only occurred with correct responses; incorrect responses prompted a review of the information before repeating the question. Telephone interviews assessed usability, overall understanding, educational level and primary language. RESULTS: the patient groups had similar demographics. The IMP group (78%) had significantly higher knowledge test scores (P < 0.001) than the SC group (57%), suggesting a better understanding of the implications of surgery. This was maintained on crossover, with the SC group scores improving by 11% compared to testing before IMP (P < 0.001). The initial IMP group scores were unchanged on crossover and repeat testing (P < 0.05). CONCLUSION: IMP provides better patient understanding than SC for RP, by ensuring that the procedure and risks have been explained consistently, and by actively testing the patient. Such tools assist in obtaining ethical and legally informed consent, thus increasing patient knowledge whilst reducing patient anxiety and potential dissatisfaction or medico-legal consequences when less than ideal outcomes occur.