Since the introduction of parameter plane techniques by Siljak in 1964, much effort has been devoted to the application of these techniques to various control system problems. This paper concerns the application of parameter plane techniques to the design of active filter systems. Constant bandwidth curves on the parameter plane are compared with frequency response curves to validate the constant bandwidth curves as accurate representations of active filter performance. This in turn implies that the constant bandwidth curves can be used in the design of active filter systems. Also presented is an example of the use of constant zeta and omega curves on the parameter plane to manipulate the pole locations of individual circuits to achieve to achieve a desired overall system configuration with the proper frequency scaling.