During the fall of 1993, a field experimental study on marine aerosol properties and thermal imager performance was conducted in the Dutch coastal waters. Aerosol and meteorological instruments, as well as thermal imagers and calibrated targets, were used at several platforms and locations: the Dutch Meetpost Noordwijk (a tower 9 km from the Dutch coast), a beach station in Katwijk, the oceanographic research vessel Hr. Ms. Tydeman, a Lynx helicopter, a P3 Orion, the NCCOSC RDT&E Div airborne platform, and buoy systems. This network of instrumentation was used for obtaining a comprehensive data base of aerosol size distribution profiles and relevant meteorological variables throughout the marine atmospheric boundary layer. Thermal imagery has been included to provide ground truth for assessing the low- level propagation effects near the ocean surface. Measurements have been made of atmospheric turbulence and refractivity effects at wavelengths in the IR and visible, to assess the marine boundary layer effects on the degradation of thermal images. Calibrated targets at different altitudes were observed to the maximum observable range under a wide variety of conditions in both the 3 to 5 and 8 to 12 micrometers bands. These data will be used for the development and validation of IRST models and IR ship signature models with the view of determining the effects of marine-generated aerosols, turbulence and meteorological profiles on their performance.