Detrusor underactivity, or underactive bladder (UAB), is defined as a contraction of reduced strength and/or duration resulting in prolonged bladder emptying and/or a failure to achieve complete bladder emptying within a normal time span. UAB can be observed in many neurologic conditions and myogenic failure. Diabetic cystopathy is the most important and inevitable disease developing from UAB, and can occur silently and early in the disease course. Careful neurologic and urodynamic examinations are necessary for the diagnosis of UAB. Proper management is focused on prevention of upper tract damage, avoidance of overdistension, and reduction of residual urine. Scheduled voiding, double voiding, al-blockers, and intermittent self-catheterization are the typical conservative treatment options. Sacral nerve stimulation may be an effective treatment option for UAB. New concepts such as stem cell therapy and neurotrophic gene therapy are being explored. Other new agents for UAB that act on prostaglandin E2 and EP2 receptors are currently under development. The pharmaceutical and biotechnology industries that have a pipeline in urology and women's health may want to consider UAB as a potential target condition. Scientific counsel and review of the current pharmaceutical portfolio may uncover agents, including those in other therapeutic fields, that may benefit the management of UAB.