This video presents the OMMIC process roadmap, including the characteristics of the GaN on Silicon (Si) process. The design kit for Microwave Office software, which integrates an electro-thermal model with the full EM environment required to design microwave and millimeter-wave PAs, is discussed and measured performances of various state-of-the-art PAs at 30, 40, and 50 GHz designed using the GaN/Si process are presented.