I am starting a travel nurse staffing company that will be placing traveling nurses and other healthcare professionals that will work in several different states and in some foreign countries.  The healthcare professional with be an employee of my company who will be contracted by the medical facility.  To protect my assets and also the income generated, I plan on creating a holding company that will own the staffing company.  I plan on incorporating in DE although I am a resident of California.  What would be the best state for incorporating the two entities: the holding company and the staffing company?   Also, would I have to qualify as a foreign corporation in every state that I place someone on assignment?