Lower urinary tract dysfunction (LUTD) is an umbrella diagnosis that covers the abnormalities of anatomy and function in the bladder, urethra, and, in men, the prostate. People with LUTD face a number of social, mental, and physical health effects due to the symptoms. Despite the increasing evidence in the assessment and management of lower urinary tract symptoms, it remains a challenge to bridge the gap between research evidence and clinical practice. In this book, each and every one of the authors presents a remarkable work for how to apply the evidence to clinical practice from different aspects. I hope this book is a key for every reader to open the door to LUTD.