Most attempts at numerical synthesis of vertical seismic profiles ( VSPs) do not explicitly include the interaction of seismic waves with the borehole, the casing, or instruments located within the hole. Thus, borehole resonances, a type of tube wave that is prominent in many real VSPs, are typically missing in synthetic VSPs. Characteristics of generation and propagation of borehole resonances can be studied by including details of the borehole environment in acoustic and elastic finite-difference simulations. Specific models presented incorporate a variety of hole diameters, cased and uncased holes, the presence of geophones within a hole, a variety of source positions, the effects of local changes in hole diameter and lithology, and the mutual interaction of the response of two neighboring wells. The main conclusion is that the hole and the medium should be considered as a single coupled system as there is a continuous mutual transfer of energy between them.