Current methods available to measure Blood Alcohol Concentration (BAC) and the biological response of alcohol in individuals are mostly limited to cumbersome breathalyzer or blood tests. The NIAAA seeks a wearable or otherwise discreet device capable of measuring, recording, and storing blood alcohol levels in real time. Alcohol biosensors that are discreet and provide continuous alcohol use monitoring will advance the mission of the NIAAA in the arenas of research, treatment, rehabilitation, and recovery. The research under this contract is toward the development of next-generation, wearable continuous alcohol monitoring (CAM) technology designed to measure, record, and store Blood Alcohol Concentration (BAC) in real time. This SBIR “Fast-Track”-type contract contains a base contract requirement for an SBIR Phase I Study and a contract option for an SBIR Phase II Study. The SBIR Phase I Study (base contract requirement) will perform analysis toward validating the technology of a new, discreet, wearable, stable, selective and highly sensitive enzymatic biosensor and algorithms that can detect alcohol in real-time and directly from interstitial fluid and evaluate its concentration in a mixture similar to human serum. The SBIR Phase II Study (contract option) will further refine and optimize the performance of the sensor probe and integrate it into a compact, lightweight prototype device ready to use in research studies that will effectively demonstrate its potential to private investors to support commercialization.