Small bitumen droplets, roughly 10 to 40 mu m in diameter, constitute a significant fraction of the total hydrocarbon in an oil sands flotation process. In this study, the aeration of such droplets is examined-both from a surface energetic perspective as well as from direct observations. The spreading coefficient associated with bitumen aeration is evaluated based on in situ measurements of interfacial and surface tensions. In addition, micropipette techniques are employed to monitor the aeration process and to quantify the probability of aeration. Our results suggest that a positive spreading coefficient does not always guarantee the aeration of bitumen droplets, and that such a process may best be described from a statistical stand point.