Abstract The management of low risk prostate cancer, defined as Gleason’s sum ≤6, PSA <10 ng/ml, and clinical stage T1c to T2a, remains controversial. There is substantiating evidence to suggest that a subset of early stage, low risk cancers can cause significant patient morbidity and death in the long term. Studies have shown that the natural history of untreated prostate cancer is to progress, particularly after 15 years of followup. The majority of men seeking definitive surgical treatment in contemporary series fall within 55 to 65 years of age and are expected to enjoy an overall life expectancy ranging from about 15 to 30 years, placing these men at long-term risk for disease progression and prostate cancer-specific death if managed expectantly. During the past 2 decades, refinements in surgical technique and in the delivery of external beam radiation have resulted in excellent long-term cancer control and favorable quality of life outcomes following treatment. Active surveillance with selective delayed intervention assumes that an individual’s cancer will not progress outside the window of curability during the surveillance period, that markers for disease progression are reliable, and that patients are compliant. Until we understand better the long-term natural history of untreated prostate cancer, have more reliable and accurate markers to detect disease progression with certainty, and can risk stratify more precisely the subgroup of men with low risk cancers who will eventually succumb to their disease, early definitive therapy seems prudent.