The design and development of a novel opto-mechanical strain sensor-called FlexPatch-based on the use of an optical fiber Bragg grating (FBG) mounted into a custom-made miniature metallic flexure is reported. The FBG sensing element is attached to a carrier flexure using proprietary bonding process which ensures a linear, drift-free and repeatable strain response even under severe moisture and temperature conditions. The sensor is uncompensated for temperature effects, but has undergone extensive mechanical and environmental testing and is qualified for use in a strain range of +/- 2,500με with a gage factor of 1.2pm/με over a temperature range from -40° to 120°C, and a fatigue life >100x106 cycles. The FlexPatch is intended for use in diverse sensing and monitoring applications and can be installed onto surfaces by epoxy bonding or spot welding.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.