The objective of this paper is to present a process for improving the planning of gas field development. We discuss how static and dynamic characterization can be combined to help optimize gas field development. The main concepts, methodologies, and results are shown for an actual Mexican gas field. Static characterization centred on a series of seismic amplitude maps constructed from 3D seismic interpretation. Dynamic data included production data and initial pressure gradients which were useful in delineating individual reservoirs and establishing hydraulic communications between certain reservoirs. The seismic amplitude maps, modified by considering the dynamic data, improved the evaluation of reservoir quality, the estimation of drainage areas, original gas-in-place, and proved reserves. A strategy for the optimal field development was designed by using this combination of seismic amplitude maps modified with information from logs, cores, production, and pressure data.