Background: Bladder and bowel dysfunction (BBD) is characterized by lower urinary tract symptoms accompanied by bowel complaints. BBD is a common condition in childhood. The present treatment strategy for BBD is a step-wise approach starting with management of bowel symptoms before initiation of standard urotherapy and further medical treatment of LUTS symptoms. This is, however, based on clinical experience and few retrospective, non-randomized studies and high-level evidence of the succession of the elements in treatment of BBD children is missing. Our microbiome, and its role in health and disease, has gained increased focus during the past years. Studies suggest the urine and gut microbiome to be critical for maintenance of a well-functioning bladder- and bowel system. The microbiome in children is only sparsely investigated and its role in BBD is to the investigator's knowledge still unexplored. Study 1: Aim: To investigate if combination therapy is more effective in treating urinary incontinence in BBD children. Materials and methods: A prospective randomized multicentre study on children with BBD (n=100) between 5-14 years and 9 months old. They are randomized to: 1) Medical treatment of bowel symptoms (n=50) or 2) Medical treatment of bowel symptoms combined with standard urotherapy. The effect of treatment will be evaluated after 3 months. Primary endpoint: Resolution of incontinence after treatment. Secondary endpoint: Improved quality of life after successful treatment of urinary incontinence. Study 2: Aim: To investigate the urofecal microbiome in children with BBD Materials and methods: 1. A cohort study to investigate, whether the urofecal microbiome can predict response to treatment and whether it changes during treatment period 2. A case control study to investigate whether the urofecal microbiome is different in children with BBD and recurrent UTI 's and children with BBD without recurrent UTI 's. The study population consists of children with BBD included in study 1. A urine-, stool sample and a perineum swab will be collected from all participants before and after treatment. Bacterial DNA will be extracted and the microbiome will be determined. Perspectives: BBD is a common condition in childhood. It is associated with a considerable psychological burden and a risk of more severe physical complications. The studies will provide basic knowledge about characteristics of the BBD patients and contribute new information about the optimal treatment of BBD children.