his three-day workshop has the primary goal to share knowledge, case studies, techniques and workflows pertaining to the understanding and prediction of hydrocarbon seals for exploration and production in the Middle East. These seals range in age from Pre-Cambrian to Tertiary. Seals are a fundamental element of any hydrocarbon accumulation, and can control trap integrity, migration and charge volumes; the lateral and vertical distribution of hydrocarbons in a trap; percent fill (or spill) of a reservoir; and the flow of hydrocarbons from the trap during production. As such the long term economic success or failure of an exploration to development project is very dependent on seal risking. Thus consideration of subsurface hydrocarbon seals should have a high priority early on in any subsurface evaluation programme. In many areas, despite the clear importance of seals, they often remain the least studied and integrated element of the petroleum system and are also subject to lasting dogmas (e.g. the thicker the seal the greater its capacity to seal). Elements that contribute to making seals effective, such as lithology, their brittle-ductile nature, the hydrocarbon column length, the pressure regime and trap type will be reviewed. Both vertical and lateral seals must be identified when exploring for subtle and stratigraphic traps. Seals created by faults and other types of seals will be reviewed. Quantification of effective seals and an ability to predict seal capacity before drilling is key to safe and successful exploring. In terms of seal assessment, understanding and predicting hydrocarbon seals is typically a multidisciplinary task requiring geosciences and engineering to collaborate on both dynamic and static data. In many areas of the Middle East our approach to understanding seals varies and it is now time to come together, share what we think and we know through the exchange of workflow, technique, and case study examples. The outcome of this workshop will enhance our collective understanding of our hydrocarbon seals that may enhance our ability to develop new exploration concepts and make hydrocarbon discoveries.