Sandstones deposited in deep marine environments form important hydrocarbon reservoirs in many basins throughout the world. However, despite the plethora of outcrop studies and the development of numerous submarine fan models and classification schemes, very few applied studies at a reservoir scale have been published. This publication has arisen from the perceived needs of the academic and industrial communities to understand the controls on the architecture and geometry of deep marine clastic reservoirs. A number of areas of concern have been addressed: (1) Are conceptual models applicable to understanding sandstone body development and distribution at a reservoir scale? (2) Do we understand the processes that are active in the formation of deep marine clastic systems and the likely influence of these processes on reservoir quality? (3) How do we correlate and at what scale do correlation mechanisms work within and between deep marine clastic reservoirs? (4) How can we quantify heterogeneity and reservoir quality within these reservoirs?