A free brochure featuring a tutorial on single- and dual-plate capacitive sensors and applications is available from PI (Physik Instrumente), an Auburn, Mass. maker of ultraprecision motion control and sensing equipment for biotechnology, nanotechnology, photonics, semiconductor and life science applications. Capacitive sensors perform high-precision, noncontact measurements of geometric quantities representing displacement, separation, position, length or other linear dimension against any kind of electrically conductive target. The brochure features overviews on these topics: measuring displacement with nanometer precision; nanopositioning, closed-loop systems; parallel metrology, high-precision multi-axis measurements; measuring straightness and flatness, active cross-talk compensation; out-of-plane measurement, constant-height scans, out-of-round measurement; tip-tilt measurement and compensation; measuring vibration, flatness, thickness; force sensors with micronewton sensitivity; and layer thickness measurement with submicron accuracy. It may be ordered from PI or can be downloaded at: www.physikinstrumente.com/en/products/capacitive_sensor/index.php