The combustion of zirconium foils in an oxygen environment was investigated for foils ranging in thickness from about 22 to 124 μm and for oxygen partial pressures ranging from about 0.3 to 0.9 atm. Temperature profile measurements showed indications of an after-burn, which became especially significant in the combustion of thicker foils. The dependence of the combustion wave temperature and velocity on the oxygen partial pressure was determined. For any partial pressure, wave velocity decreased with an increase in foil thickness. Wave propagation in this system is a complex process and is dictated by oxide formation and oxygen dissolution. The results are examined in light of a finite difference model.