Nearly 1 million people and $1.5 billion of trade entered the United States through 328 POEs on an average day in fiscal year 2013. CBP, within the Department of Homeland Security (DHS), has four trusted traveller programs -- Global Entry, NEXUS, SENTRI, and Free and Secure Trade (FAST) -- to provide for expedited travel through dedicated lanes and kiosks at POEs. This book addresses trends in enrolment and program use over the past 5 fiscal years; the extent to which CBP has designed and implemented processes to help ensure consistent and efficient enrolment of applicants; and the impacts of the programs on travellers and CBP. GAO analysed data on enrolment and POE operations from fiscal years 2009 through 2013, reviewed documents, and visited nine POEs selected based on traveller volume and location.