Hollow optical waveguides have some unique properties compared with their solid core counterparts. These include very broad waveband, high power transmission characteristics in conjunction with extremely low interfacing and propagation losses. Such characteristics provide considerable potential for novel electro-optic and infrared devices and systems. In conjunction with discrete micro-optical components hollow waveguides have been used to demonstrate integrated circuits which are the optical analogue of the electronic PCB. The underlying physics and technology of hollow optical waveguides will be discussed in the context of a wide range of applications.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.