This paper discusses advancements that have been made in scanning microwave impedance microscopy (sMIM) and how they are being used to measure various electrical properties in semiconductor devices. It explains that sMIM has a sensitivity of less than 0.1 aF and can measure minute changes in dielectric constant (k-value) and distinguish dopant levels over a wide range of concentrations with a spatial resolution of a few nm. For dielectric films and dopant levels, measurements are conveniently given in log-linear form with a repeatability well within the typical requirements for process monitoring. This, in turn, has enabled reliable quantification, where once only qualitative information was provided. The paper presents real-device results representing a wide range of measurement scenarios.