Abstract Infrared optical chemical sensing has been significant program of research at the BHP Research Laboratories over the past 10 years. Major developments within the program are described in this paper. The program commenced with the development of FT-IR/software techniques for rapid characterization of mineral species in the laboratory. This work, which saw the development and licensing of CIRCOM software, subsequently led to field trials of on-line FT-IR spectroscopy for minerals characterization and was then extended to the characterization of used lubricating oils. A major activity within the program has been the investigation of methods for the measurement of methane and other gases in an underground coal mine using optical fibres, and the development and testing of a multipoint infrared-based system for coal-mine methane monitoring. Details of the system and its performance are described. Other activities within the program have included laboratory investigations of pulsed laser remote spectroscopy techniques for detection and ranging of methane gas leaks at LNG installations, and the measurement of the composition of liquid hydrocarbon mixtures by optical fibre-based spectroscopy. More recently, the application of IR spectroscopy for characterization of wastewaters containing cyanide species has been investigated within the program. IR spectroscopy is also being used as part of a preliminary screening protocol for waste products that require characterization and then development of appropriate treatment procedures.