The quartz crystal microbalance (QCM) is seeing a rapid increase in new applications and new instrumentation techniques. It is increasingly evident that this sensor provides not only mass data, but can provide information relative to the mechanical properties of deposited Films as well. Determining film properties from the measured electrical properties of the QCM resonator requires a modeling of the effects of the film on the electrical behavior of the resonator. We show that the complete electro-mechanical model can provide descriptions of the effects of film properties on resonator behavior in a number of formats to include not only the standard steady-state behavior, but also the transient responses used in a recent new measurement technique. The use of a single model for all techniques will permit comparisons among the results. (0 2002 Published by Elsevier Science B.V.