Benign prostatic hyperplasia (BPH) is one of the most common diseases to affect older men.Histological (microscopic) BPH, which is characterised by both stromal and glandular hyperplasia, is present in more than 60% of men beyond their sixties. More than 40% of men in this age group have lower urinary tract symptoms (LUTS) and about half this group have impaired quality of life. The prevalence increases with age, and the overall number of patients affected is rising worldwide as populations age. At current intervention rates, about one-fifth of patients with symptomatic disease who present to a doctor will eventually be treated surgically, although this may be falling. The remainder will often be managed initially by watchful waiting. However, the majority of these individuals suffer gradual progression of symptoms and the bother associated with them, and increasingly require treatment either with medication or surgery. [With external links to the evidence base]