Nocturia, generally accepted as an inevitable consequence of aging, is also a symptom of a potentially lethal condition--obstructive sleep apnea (OSA). The descriptive study reported in this article examined nocturia and sleep-related breathing problems in persons with postpolio syndrome (PPS) and tested the Sleep Disordered Breathing--Nocturia Model. This model describes the cascade of events that results in polyuria in persons with sleep-related breathing disorders. Data were analyzed with descriptive and inferential statistics. A 34-item questionnaire was published in the newsletter of a national polio support group, and the 584 respondents constituted a convenience sample. The results showed statistically significant associations between OSA symptoms, nocturia, poor sleep quality, daytime sleepiness, lower urinary tract symptoms, naps, and decreased self-rated health. Study limitations were the use of a convenience sample and possible self-selection of persons with more severe sleep and bladder problems. The results support the model and document how nocturia and sleep disturbances negatively impact persons with PPS.