More than 100,000 people suffer from functional urinary incontinence in Japan. To improve the quality of life of these people, we tested a device for monitoring micturition by means of a thin-layer membrane sensor in a diaper. The device was tested in elderly inpatients, and associated changes in the wordload of the nursing staff were also recorded. The device was beneficial because the precise micturition time was easily obtained and thus the daily pattern of micturition became obvious. With the use of this device, the time during which the patients wore wet diapers was shorter than with the conventional system of scheduled changes. However, the increase in the frequency of diaper changed doubled the workload of the nursing staff. In conclusion, improving the quality of life with regard to urinary incontinence entails an increase in the workload of the nursing staff; efficient distribution of that work may require some staff members to devote all their time to changing diapers.