Vilella, who was also a renowned architecht, had ocuppied the position of mayor of San Juan before becoming Governor. He and Muñoz Marín were close collaborators, and he gained Muñoz Marín's trust.
During his period as Governor, Sánchez Vilella was known for trying to change his party's facial make up, pushing for younger blood to come up in the party's organization. It could be argued that Vilella might have been influenced by the youth movement that the island was experiencing country wide during the 1960s, a period where many social areas in Puerto Rico, including television, music and sports, were being introduced to fresh, younger personalities. Because of his revitalization ideas, he was not allowed by his party to run again for governor in '68, and many members of the party left, to form the shortly lived Partido Del Pueblo (The Public's Party), which lost in the election, but caused a considerable percentage of PPD voters to vote for them, indirectly helping Luis A. Ferré and his PNP party to win the elections that year.
After leaving La Fortaleza, Sánchez Vilella lived a relatively quiet life, until his death in 1998.