Over the last several years, microseismic (MS) monitoring has quickly grown as a technology to map various reservoir processes. Imaging hydraulic fracture stimulations is the most common application especially within North America. As indicated in the introduction to this special section, initial interest in MS was primarily in the engineering community. As the method was pushed forward by the engineers, geophysicists within operating companies began to get pulled in to support the engineering projects. As application of the method gathered steam, interest expanded in the geophysical community and into academia as seen by the growth of research consortia looking at the technique. While MS is a seismic technique, it is sufficiently novel that most geophysicists are largely uninformed about technology challenges. Nevertheless, over the last few years the geophysical community has been both educating itself and taking stewardship of the technology. MS remains a unique geophysical technology although the technology was originally adopted by engineers.