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ii The virtual source method is a technique to image and monitor below a complex and time-varying overburden without the knowledge of overburden velocities and near-surface changes. It is based on extracting the response between a given pair of receivers by correlating the wavefields recorded by them and stacking over the physical sources. There are several challenges that arise while generating virtual source data, such as the maximum allowable spacing of the physical sources, limited acquisition aperture and reflections/multiples from the overburden, that need to be addressed. Some of these challenges can be overcome by separating the wavefield into up-going and downgoing waves. Wavefield separation not only suppresses the artifacts associated with the limited acquisition aperture typically used in practice, but also helps reconstruct a response in the absence of downgoing reflections and multiples from the overburden. These improvements in removing the artifacts caused by limited acquisition aperture and overburden-related multiples are illustrated on a syntheti