Background: Nocturnal Enuresis (NE) is one of the most prevalent childhood disorders and has significant negative psychosocial impact on the child and family. Objective: To assess the characteristics of children with NE and trends over a 15-year period. Methods: The study included 18,677 children [11,205 (60%) boys and 7,472 (40%) girls] referred to a network of clinics specializing in treatment of voiding problems (Age range: 4-12 years; Mean age = 7.06) between the years 1995-2009. We analyzed socio-demographic characteristics and trends over time using a standard questionnaire administered in the clinics. Results: Over the course of the 15-year period, children were referred to treatment at a younger age (Mean age 1st period = 7.52, Mean age 2nd period = 7.12, Mean age 3rd period = 6.71) and the likelihood of referrals of younger children (4-5 years) increased (1st period = 24.5%; 2nd period = 33.6%; and 3rd period = 41.9%). More children were referred during winter than summer or transition seasons. The higher prevalence of boys was maintained across this period. In addition, girls had 34% higher chance to suffer from primary NE compared to boys and had 12% higher chance to suffer from NE only compared to boys. Birth order and children's age predicted NE type (primary/secondary) and in addition to family size also predicted enuresis pattern (NE only/combined NE and Diurnal Enuresis). Conclusions: The findings of this largest study on children referred for NE treatment provides a wider understanding of important associated factors to this phenomenon.