Attitudes toward predictive testing for Alzheimer's disease and knowledge about this disease were investigated in a group of medical and psychology students. Overall, knowledge was poor and their own chance of getting Alzheimer's disease was mostly perceived as small. About half the students thought the development of a predictive test for Alzheimer's disease important, while the other half held the opposite view. Considerable variability was also observed in the judgement of the (dis)advantages of such a test. Only a minority of the students would like to have a predictive test themselves. Important arguments against a predictive test concerned the absence of a treatment for Alzheimer's disease and the emotional burden of a positive test result. Arguments in favour dealt with the ability to make plans for the future and to prepare oneself for the disease. The divergence in attitudes and opinions reflects the complexity of predictive testing for Alzheimer's disease. Stepwise regression revealed that knowledge about Alzheimer's disease and, to a lesser extent, risk perception are significant predictors of attitudes toward predictive testing. However, they only explain a small part of the variance in attitudes. Moreover, why attitudes are less positive when knowledge and perceived susceptibility increase is not clear.