Monitoring hydraulic fracture stimulations from the surface is a technique that, in the past, met with mixed success. One reason for this experience is that the measurement has often been treated as if it were only a minor variant of the reflection surveys our industry is most familiar with. While reflection seismic sources are designed to generate primarily P-waves, fracturing rocks emit both P- and S-waves with the much larger proportion of energy as S-waves. To capture the information content in the microseismic wavefield, surveys must be designed to record, and processing strategies designed to use, the full vector wavefield energy emitted by the fracture process. To record the full vector wavefield requires the use of appropriate sensors capable of recording low frequencies and three components.