A study is presented in which conditioning is successfully used by a houseparent as a treatment for chronic nocturnal enuresis for a child in a residential facility. Data are plotted over an extended period and the point is made that, though the effect of the conditioning treatment was rapid and pronounced, persistence on the part of worker and child is needed if such procedures are to be applied properly. The effects of the method on other children in the facility, the results of changes in houseparents and fluctuations in bedtimes, and the cost of the program are discussed.