Reservoir monitoring can be applied on small fields but has been (to date) mainly applied on large fields and deepwater operations where its impacts have such a large potential impact that economic justification is easy. The field development planning and operations management of such fields is now almost invariably assigned to integrated asset teams comprising reservoir and production engineers, geologists, geophysicists and other specialists such as geomechanics and petrophysics experts. The expertise for the technology of reservoir monitoring is often best known by subsets of this team. While the production or completions engineer may best understand downhole measurements, the petrophysicist may be the expert in production logging, the geophysicist in 4D seismic, the geologist in the static model construction and the reservoir engineer in pressure transient analysis and reservoir simulation.