Abstract The recently developed IMET (improved meteorology) system for ships and buoys and the key elements of the program that led to its development are described. The system improves the ability to measure mean meteorological variables, including wind velocity, barometric pressure, incoming shortwave and longwave radiation, air temperature, sea surface temperature, humidity, and precipitation, from both types of platforms. Extensive laboratory and field tests of a variety of sensors were conducted to investigate and document their stability, accuracy, and reliability. Modular electronics were developed so that each sensor in the system communicated digitally, returning calibrated values to a central data recorder. IMET systems have been deployed on buoys in the Atlantic and Pacific Oceans and on research vessels. The history of the program, reasons for the choice of the present sensor suite, the design of the sensor modules, a description of the data acquisition system, and examples of data collected w...