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35 Background: SBRT is an emerging treatment for prostate cancer, but long-term reporting remains sparse. We present a prospective Phase II trial with 90% treated in community facilities. Methods: 14 institutions enrolled 259 patients - 112 low-risk; 147 intermediate-risk. The regimen emulated a high-dose rate brachytherapy (HDR) regimen - 38 Gy/4 fractions delivered by robotic SBRT. Androgen deprivation therapy was not allowed. HDR-like heterogeneous prostate dosing was used (Dmax >57 Gy). Toxicities were assessed by CTCAE v3.0 and quality of life assessed by Expanded Prostate Cancer Index Composite (EPIC). Biochemical recurrence was defined by Phoenix criteria. Results: Median follow-up is 5 years. 5-yr Grade 2 GU toxicity was 13.7% and GI toxicity 4.5%, with Grade 3 rates of 3% (GU) and 0% (GI) (one Gd 4 GU event). 5-yr median PSA was 0.1 ng/mL with further subsequent decrease (7 y = 0.035 ng/mL). 5-yr biochemical disease-free survival (bDFS) = 100% for low-risk and 88.5% for int-risk. 6 patients developed distant metastasis and one died of disease. Median EPIC GU obstruction and GI scores were similar at baseline vs. 5 years. 2% of patients had baseline GU incontinence requiring pad use vs 10% at 5 yrs. Of baseline potent men, 46% remained so at 5 yrs (66.7% for those age ≤65 vs. 37.1% age >65 at treatment). Conclusions: This is the first report of 5-year median follow-up outcomes post heterogeneous dosing SBRT for early prostate cancer. This treatment produces a low PSA nadir vs other forms of radiotherapy, with a favorable long-term result that appears reproducible in the community. Clinical trial information: 00643617. [Table: see text]