Managed Pressure Drilling (MPD) has gained industry acceptance with surface BOP stacks where improved control of downhole pressure has been achieved. The industry is currently beginning to see implementation of MPD systems in deepwater environments where narrower drilling margins make improved pressure control even more important. Despite the evident need for such applications the industry has been slow to fully utilize MPD techniques in deepwater. The question this paper seeks to address is, "What is preventing us from employing the same MPD systems currently being used with surface stacks in a deepwater environment?" This question encourages challenging conventional modes of thinking in the industry concerning risks pertaining to risers and well control when utilizing MPD systems. This paper draws on some of the difficulties, thinking, and achievements when such a system was implemented for drilling a deepwater GOM well. MPD in deepwater involves new equipment, capabilities, and risks. Full utilization of MPD systems in a deepwater environment requires re-thinking several things including primary well control and the conditions to which the riser is exposed.