Payment for home hemodialysis aides has been proposed as a means of inducing shifts from center hemodialysis to less-expensive home hemodialysis. By using a simulation model, we computed the cost per life year of end-stage renal disease care when changes in the proportions of patients treated by center for home hemodialysis are brought about by paying for home hemodialysis aides. If all home hemodialysis patients receive payment for aides, total costs will increase unless there are sufficient shifts from center to home hemodialysis to offset the increased costs. The cost-effectiveness of home hemodialysis aides is critically dependent on who receives a paid aide, the salary of the aid, and the number of patients who move from center to home hemodialysis. Poorly formulated regulations may jeopardize the cost-effectiveness of home hemodialysis and increase the total cost of end-stage renal disease care.