In Reply We share the anxiety expressed by Schooling et al about conducting a large-scale randomized trial of testosterone therapy for frail, older men with hypogonadism, given the existing evidence of important harm. The best evidence of harm is from the Testosterone in Older Men With Mobility Limitations (TOM) trial,1 which randomized community-dwelling men 65 years and older with limitations in mobility and total serum testosterone levels lower than 350 ng/dL (to convert to nanomoles per liter, multiply by 0.0347) to placebo or testosterone gel (Testim 1%; Auxilium Pharmaceuticals Inc) for 6 months. The data safety monitoring board stopped the TOM trial early because of harm—more atherosclerotic events (myocardial infarction, sudden death, angioplasty, coronary artery bypass, or stroke) and more cardiovascular events (atherosclerotic events plus syncope, arrhythmias, peripheral edema, elevated blood pressure, and electrocardiographic changes).