Air bubble - bitumen attachment is a critical step in the flotation of bitumen from mined oil sand. In this study, single bubble - bitumen drop attachment was observed directly using a novel experimental technique. Induction time is determined and used as an indication of bubble-bitumen attachment potency for both hydrogen and oxygen bubbles. The attachment tests were conducted in deaerated municipal water (City of Edmonton tap water) at temperatures ranging from 22-50 degreesC. Induction times measured for hydrogen bubble attachment were shorter than those for oxygen bubbles. Coalescence tests were also conducted in the absence of bitumen, and showed that hydrogen bubbles coalesced more rapidly than oxygen bubbles in both deaerated municipal water and clear (solids-free) process water.