The need for sensors demonstrating both high sensitivity and electromagnetic noise immunity has prompted the development of sensing systems based on optical fiber technology. This presentation opens with a short review of fiber optic sensing methods, including a discussion of several devices developed in prominent laboratories. The theoretical and empirical results of a particular technique of distributed pressure sensing appear next. This sensing approach, aimed towards the nondestructive testing of graphite/epoxy composite structures, relies on optical time - domain reflectometry in imbedded optical fibers. The method is investigated primarily in terms of its sensitivity and its effect on the mechanical integrity of the host composite. The work concludes with a discussion of results and ideas relating to microbending sensor research, as well as the design of several novel sensing devices. / M.S.