Du Ruhui
Later in 621, when Emperor Gaozu, awarding Li Shimin for his great accomplishments, bestowed on him the unprecedented title of "Grand General of Heavenly Tactics" (天策上將, "Tiance Shangjiang"), Li Shimin built a mansion where he housed those staff members with the best literary talent, supplying them with the best food and supplies and had them conduct research and writing. Fang was part of this establishment, along with, among others, the fellow future chancellors Du Ruhui and Xu Jingzong. When Du was subsequently commissioned as a prefectural secretary general, Fang told Li Shimin that Du was an uncommon talent that he should do everything he could to retain, and Li Shimin thus persuaded Emperor Gaozu to allow Du to remain on his staff. It was said that Fang was capable in planning and strategizing, but not decisive in his decisions, while Du was capable in making quick and correct decisions, and they divided their strategical responsibilities while on Li Shimin's staff in that manner. (This eventually led to the Chinese proverb "Fang plans and Du decides" (房謀杜斷, "Fang mou Du duan"), after they became renowned.)