The U.S. Navy Office of Naval Research (ONR) is developing electro-optical (EO) sensor testbeds based on second-generation infrared (IR) focal plane array (FPA) technology, to be used for research and system demonstration in both shipboard and airborne applications. These technology-base sensors will demonstrate the functionality as well as many of the operational characteristics necessary ultimately in fielded infrared search and track (IRST) systems. The shipboard application involves the augmentation of existing and developmental radar assets in countering the advanced, sea-skimming, anti-ship missile (ASM) threat for mast-mounted use aboard high-value surface combatants. The ONR shipboard IRST testbed, the focus of this paper, currently is completing development, integration, and testing activities; BDM Federal (Arlington, Virginia) has supported these activities under contract to ONR over the past three years. The shipboard IRST testbed employs two separate, scanning FPAs covering the long wavelength IR (LWIR) and medium wavelength IR (MWIR). Preliminary test results show both a good correlation to predicted performance and a high level of absolute performance in terms of sensitivity and stabilization.