In this review, Klotz and Dall’Era summarise available data from the Toronto, UCSF, ERSPC, PASS and Royal Marsden active surveillance cohorts, looking specifically at outcomes of patients classed as intermediate risk. Cancer specific survival in men managed initially with active surveillance was found to be similar to results published with immediate radical intervention. However, definitions of intermediate risk varied from cohort to cohort. Toronto data found that 44% of patients who progressed on active surveillance were Gleason 7 at diagnosis. ERSPC data showed that 10-year treatment-free survival was higher in the low-risk cohort but there was no difference in 10-year disease-specific survival. Overall survival was higher in the low-risk cohort. The authors recommend that patients with more than very minimal Gleason pattern 4 should be subject to enhanced monitoring due to the possibility of increased risk of metastatic disease. New data from novel biomarkers and imaging improvements may assist in identifying those at highest risk.