On August 11, 2011 the Ninth Circuit published United States v. Aguila-Montes de Oca (“Aguila-Montes”), -- F.3d. --, 2011 U.S. App. LEXIS 16532 (9th Cir. 2011) (en banc). Aguila-Montes made two holdings, one of which is applicable to the categorical approach generally, and one of which addresses when California burglary meets the definition of “burglary” for aggravated felony purposes. This Advisory addresses the categorical approach; a separate Advisory at www.ilrc.org/crimes addresses burglary.