Androgen suppression - the inhibition of testosterone and other male hormones - is a routine therapy for prostate cancer. Unfortunately, it can dramatically reduce the quality of patients\' sex lives and, more importantly, lead to cancer recurrence in a more deadly androgen-independent form. A new paper combining mathematical modeling with clinical data validates a different approach: cycling patients on and off treatment. Such intermittent androgen suppression alleviates most unwanted side effects and postpones the development of resistance to treatment. With the model, the authors say, clinicians can predict the maximum length of treatment for a given patient before they become resistant, leading to more effective therapy.