With the number of airplane passengers using U.S. airports expected to grow to 1 billion by the year 2015, ground access to U.S. airports has become an important factor in the development of our nation's transport. networks. Increases in the number of passengers traveling to & from airports will place greater strains on our nation's airport access roads & airport capacity, which can have a number of negative economic & social effects. This report addresses the development of intermodal capabilities at U.S. airports, incl.: (1) the roles of different levels of gov't. & the private sector; (2) the extent to which such facilities have been developed; (3) benefits, costs, & barriers to such development; & (4) strategies to improve these capabilities. Charts & tables.