It is important to be able to accurately evaluate the electrical properties of dielectric materials to enable the accurate design of passive microwave integrated circuit components. This paper reports on research that has been undertaken in this area at London South Bank University. Three measurement techniques are reported. The first is a novel technique for measuring dielectric materials with a large tan δ using a composite resonator. The second is the measurement of the permittivity of ferroelectric thin films using a planar capacitor. The third is the use of an evanescent microwave probe to find the electrical properties at the surface of a sample.