The trial will compare the efficacy and safety of concomitant chemoradiation with tirapazamine, cisplatin and radiation versus cisplatin and radiation.

Inclusion Criteria:

• Previously untreated squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx.
• Stage III or IV disease (excluding T1N1, and T2N1).
• ECOG performance status less than or equal to 2.
• Absolute neutrophil count at least 1.5 X 10^9/L, platelet count at least 100 X 10^9/L, and hemoglobin > 9g/dL.
• Serum bilirubin < 1.25 times ULN and AST/ALT < 2.5 times ULN.
• Calculated creatinine clearance (Cockcroft-Gault) > 55 mL/min.

Exclusion Criteria:

• Metastatic Disease