The current invention provides improved methods and compositions for completing a well bore. In one aspect, the current invention provides a process for preparing a foamed cement composition. The process utilizes air to foam the cement after the air has been treated to lower the oxygen content below that concentration necessary to support combustion. Additionally, the current invention provides a process for completing a well bore using foamed cement wherein the foam is generated with reduced oxygen content air. Finally, the current invention provides a foamed cement composition wherein the gaseous portion of the composition is air having a reduced oxygen content.