Northrop Grumman Corporation has made significant progress in the development of compact, high power, continuous operation solid state lasers for military applications during the past six years. The Joint High Power Solid State Laser (JHPSSL) program is nearing completion of its third phase; its key objective is to demonstrate a 100kW solid state laser with excellent beam quality. Northrop's unique scalable architecture coherently combines modular 15kW lasers to produce power levels of 100kW and beyond with excellent beam quality and run times. This paper describes the JHPSSL program history, Northrop's high power solid state laser architecture and our demonstrated results.© (2009) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.