Book excerpt: Gas Wettability of Reservoir Rock Surfaces with Porous Media compiles critical information on this complex topic, thus helping engineers more successfully face technical field challenges in oil and gas recovery. Combining both theoretical and practical knowledge, this concise reference bridges basic concepts with factors affecting gas wettability, also covering polymer-type gas wetting reversal agents in technical detail and discussing gas wettability's influence on capillary force, oil-water distribution, and gas wettability's application in petroleum engineering operations from both domestic and international projects. This book delivers the critical concepts, methods, mechanisms and practical technology needed for today's complex oil and gas assets. - Helps readers further develop and improve basic theory on petrophysics and reservoir engineering - Covers various aspects, like the developmental history of gas wettability and the concept and evaluation of gas wettability of oil and gas reservoir rock surfaces - Creates a bridge between theoretical knowledge and practical application, with content covering new theories, methodologies and the technologies used in drilling, completion and reservoir engineering