Microelectromechanical systems on a scale as small as a few micrometers can be fabricated using photolithographic and anisotropic etching processes on single crystal substrates such as silicon. Processing steps similar to those used to fabricate integrated circuit chips are used to form these three-dimensional structures. This mini-symposium will examine the underlying physical principles, fabrication processes, and applications for this new technology. Special emphasis will be placed on applications and potential applications in the life sciences and clinical medicine.