The steam-foam process is an enhanced oil recovery (EOR) method which improves the performance of a traditional steam drive using a foaming surfactant. In this study, the surfactant solution was coinjected with steam at a certain quality into a core holder filled with a sand pack. The core holder was kept inside an oven at 250 degrees C to mimic the near-wellbore temperature in a steam flood. By measuring the pressure drop along the core with and without the surfactant, the mobility reduction factor (MRF) of the generated foam was measured. Two different surfactants were used, and the effect of different parameters such as pressure, steam quality, and superficial gas velocity on the foam strength was studied. Some mechanisms have been suggested to explain the foam generation delay and the foam front retardation in the core. In the modeling section of this paper, the current STARS model for foam generation was studied and its shortcomings identified based on the experimental observations. A modified foam model has been proposed and used to simulate the core-flooding results.