Rigo 23 is a Portuguese muralist, painter, and political artist residing in San Francisco, California. Although he is known particularly in the San Francisco community for having painted a number of large scale Pop Art inspired "one way" sign murals, such as the "One Tree" mural on the U.S. Route 101 onramp at 10th and Bryant Streets, the "interstate route sign" shaped Innercity/Home adorning an affordable housing high rise in downtown S.F., or the "Sky/Ground" mural at 3rd and Mission Streets, the bulk of RIGO's work more literally highlights world politics and political prisoners from the Black Panthers and the Angola Three to Mumia Abu-Jamal, whose conviction for the murder of a policeman is contested, and the American Indian Movement's Leonard Peltier. He is one of the founding members of Clarion Alley Mural Project collective and is still an active member as of 2006 as well as an occasional professor at The San Francisco Art Institute. He has also designed several installations as part of the 2006 Liverpool Biennial. He is considered by some art critics and curators to be part of the first generation of the San Francisco Mission School art movement.