This brief is the third in a series describing commuting in America. This body ofwork, sponsored by American Association of State Highway and Transportation Officials(AASHTO) and carried out in conjunction with a National Cooperative Highway ResearchProgram (NCHRP) project that provided supporting data, builds on three prior Commutingin America documents that were issued over the past three decades. Unlike the prior reportsthat were single volumes, this effort consists of a series of briefs, each of which addresses acritical aspect of commuting in America. These briefs, taken together, comprise a comprehensivesummary of American commuting. The briefs are disseminated through theAASHTO website (transportation.org). Accompanying data tables and an Executive Summarycomplete the body of information known as Commuting in America 2013 (CIA 2013).