We present the impact of systematic radiation dose escalation from 64 Gy to 66 Gy to 70 Gy on the outcome after radiation therapy (RT) alone or combined with hormonal treatment (HT) in a series of 494 consecutive localised prostate cancer patients treated during 1990-1999. Prognostic factors for prostate-specific antigen (PSA) failure, overall survival (OS) and prostate cancer specific survival (CSS) were investigated using multivariate analysis. T stage, pre-treatment PSA, grade, radiation dose and HT were found to be independent predictors of PSA failure. T stage, grade and HT were also independent predictors of both OS and CSS, while radiation dose was a significant predictor for OS and indicated a trend (p = 0.07) for CSS. A dose of 70 Gy combined with hormonal treatment improves PSA failure free survival and survival in localised prostate cancer compared with doses of 64-66 Gy.