In 148 head-and-neck cancer patients treated with surgery plus radiotherapy (RT), IMRT, 3D-conformal RT, and conventional RT and 10 potential prognostic factors were evaluated for overall survival (OS), metastasis-free survival (MFS), and loco-regional control (LC). On univariate analysis, ECOG performance status, T-stage, AJCC-stage, extent of resection, and pre-RT hemoglobin level (>or=12 g/dl better than <12 g/dl) were significantly associated with treatment outcome, whereas RT technique had no significant impact. On multivariate analysis, performance status maintained significance for OS (P=0.019), AJCC-stage for LC (P=0.034), extent of resection for OS (P=0.045) and MFS (P=0.021), pre-RT hemoglobin for MFS (P<0.001). IMRT was associated with less xerostomia than conformal RT and conventional RT (17% versus 63% and 73%, P=0.037). Otherwise, acute and late toxicity was similar. Outcome was significantly associated with performance status, tumor stage, extent of resection, and pre-RT hemoglobin. The three radiation techniques provided similar disease control. IMRT was effective in significantly reducing xerostomia.