A simple engineering approach for rapid simulation of cross-talk in mixed-mode IC's using SPICE is presented. A side-by-side comparison of several cross-talk reduction schemes has shown that while an SOI-based process provides high isolation from cross-talk at low operating frequencies, its benefit is lost at high frequencies. Simple guard ring substrate contacts appear to be the technique best suited for preventing crosstalk at high operating frequencies. Lumped parameter equivalent circuits have also been developed to represent different isolation schemes in SPICE. The isolation characteristics of test structures employing the above techniques are computed using SPICE and the results compared with two-dimensional device simulation. The results are also compared with experimental measurements on actual silicon to validate the models.