This retrospective study aims to quantify the relationship between 5-alpha-reductase inhibitor (5ARI) adherence / length of therapy and the likelihood of acute urinary retention (AUR) or prostate surgery in patients with benign prostatic hyperplasia (BPH) as well as the economic impact associated with these medical encounters. The Integrated Health Care Information Solutions (IHCIS) database will be utilized for this study (2000-2006).