International trade is a critical component of the U.S. economy, with U.S. goods trade amounting to about $4 trillion in 2014, with merchandise imports of $2.4 trillion and exports of $1.6 trillion (see Appendix B ). The efficient flow of legally traded goods in and out of the United States is thus a vital element of the country's economic security. While U.S. trade in imports depends on the smooth flow of legal cargo through U.S. ports of entry (POE), the goal of trade facilitation often competes with two additional goals: enforcement of U.S. trade laws and import security. How to strike the appropriate balance among these three goals is a fundamental question at the heart of U.S. import policies. Striking the appropriate balance among competing import policy goals is made more difficult due to the volume and complexity of trade inflows. U.S. Customs and Border Protection (CBP), the agency charged with managing the import process at the border, admitted about 30.4 million import entries per year through over 300 U.S. POEs, in fiscal year (FY) 2013. The largest volume of imports comes through land (truck and rail) and maritime flows, which together account for over 25 million shipping containers per year. Air cargo consists mainly of lower volume, higher value goods. This report describes and analyzes CBP's role in the U.S. import process. (The report does not cover CBP's role in the U.S. export control system.) The first section of the report describes the three overarching goals of U.S. import policy and the tension among them. Second, the report summarizes recent legislative developments and provides a legislative history of customs laws, followed by an overview of the U.S. import process as it operates today. Third, the import process and CBP's role in it are discussed. Congress has a direct role in organizing, authorizing, and defining CBP's international trade functions, as well as appropriating funding for and conducting oversight of its programs. Thus, the final section highlights several policy issues that Congress may consider in its oversight role or as part of customs or trade legislation, including measures seeking to provide additional trade facilitation benefits to importers and others enrolled in "trusted trader" programs, to improve enforcement of intellectual property and trade remedy laws, to strengthen cargo scanning practices, and/or to promote modernization of customs data systems, among other issues. U.S. import policy seeks to balance three overarching policy goals. First, import policy promotes trade facilitation . Trade facilitation refers to efforts to simplify and streamline international trade procedures to allow for the easier flow of legitimate goods across international boundaries and thereby to reduce the costs of trade. Trade facilitation includes the availability of advanced customs rulings, transparent and efficient procedures, elimination of "red tape," clear information, effective communications, and cooperation between border agencies, among other provisions. Trade facilitation is a priority for CBP and the trade community because trade represents a key component of the U.S. economy. International trade accounts for about a quarter of the U.S. economy, with merchandise trade (i.e., cargo) accounting for more than three-quarters of all U.S. trade flows. Most economic research finds that while international trade may impose short-term costs on certain sectors and industries that compete with imports, in the long run, trade promotes efficiency, reduces costs to consumers, and increases economic growth due to competitive advantage. With the production of goods increasingly organized into global supply chains, in which the manufacture and final product assembly often occur in two or more countries, intermediate components during the manufacturing process are a significant percentage of total imports and exports in most countries, and a wide variety of U.S. manufacturers depend on the efficient import and export of these inputs. Partly for this reason, trade facilitation has been a priority issue for the United States and its international partners in organizations such as the World Trade Organization (WTO) and the World Customs Organization (WCO), and in free trade agreement negotiations (FTAs). Within the WTO Doha Development Round of multilateral trade negotiations, for example, the United States has pursued "the shared objective of a rules-based, transparent, and efficient approach to goods crossing the border." In the WTO, the United States was instrumental in negotiating binding disciplines on trade facilitation included in the December 2013 multilateral "Bali Agreement." The United States and other members of the WCO are encouraging the use of electronic systems to expedite the clearance of merchandise entries and to ensure effective customs controls, including the adoption of a "single window" data system through which multiple cross-border regulatory agencies can clear merchandise entries (see " Interagency Coordination "). There is an inherent tension between efforts to promote efficient trade flows, and a second goal of U.S. import policy: the enforcement of trade laws designed to protect U.S. consumers and business against illegal imports and to collect customs revenue. In general, U.S. trade laws seek to protect U.S. consumers by enforcing health and safety standards, and to protect U.S. businesses by enforcing patent, trademark, and copyright laws and by collecting anti-dumping and countervailing duties (AD/CVD). Trade enforcement policies also govern the collection of tariffs, fees, and taxes; CBP generated more than $36 billion in revenue in FY2013, including more than $31 billion in customs duties. The third overarching goal of U.S. import policy is import security , or preventing the entry of chemical, biological, radiological, and nuclear (CBRN) weapons and related material; illegal drugs; and other contraband. While customs agencies have always played a role in protecting public safety, including through narcotics enforcement in particular, the terrorist attacks of September 11, 2001 (9/11), caused many Americans to place even greater emphasis on transportation and port security. Thus, security measures enacted after 9/11 placed additional responsibilities on customs officials to pro-actively prevent weapons of mass destruction and other threats to the homeland from entering the United States and have made import security a central feature of U.S. trade policy (see " Major Post-9/11 Import Security Legislation "). Import security also has become an important feature of international efforts, and the United States and its partners in the WCO have adopted new security protocols for tracking, inspecting, and screening containerized imports and exports. Trade facilitation is in tension with trade enforcement and import security because trade facilitation involves promoting faster and more efficient trade flows, while trade enforcement and import security involve identifying and preventing illegal flows—tasks that often involve slower cargo flows and reduced efficiency for the importer. These competing pressures make the implementation of import policy a complex and difficult task, which CBP addresses through a process of risk management, as described below (see " The Import Process "). Many policy questions with respect to the import process concern how Congress and CBP balance these three goals. Some U.S. importers and some in Congress have criticized CBP for neglecting trade facilitation in favor of import security and trade enforcement. For example, some in the trade community view the paperwork and additional reporting requirements imposed on U.S. importers as overly burdensome, and they assert that these requirements run counter to U.S. interests by threatening America's economic security. Others argue that infrastructure issues, scanning, and inspections at land ports of entry result in unacceptably long and unpredictable border wait times. Delays have been described as particularly onerous at the U.S.-Mexico border, where trade has increased more than sixfold since the North American Free Trade Agreement (NAFTA) was implemented in 1994. Several studies have estimated the economic consequences of border crossing delays, including a 2008 draft report by the Department of Commerce that estimated that crossing delays at the U.S.-Mexico border resulted in $5.8 billion in lost economic output, $1.4 billion in lost wages, 26,000 lost jobs, and $600 million in lost tax revenues—and would result in losses twice this size by 2017. A review of nine additional studies concluded that "one message comes through quite clearly—long and unpredictable wait times at the POEs are costing the United States and Mexican economies many billions of dollars each year." At the same time, others in Congress and in the trade community assert that the United States may remain vulnerable to a terrorist attack against a port of entry—with potentially catastrophic results—and that CBP should place greater emphasis on import security, even if the economic costs are high. Some Members have expressed frustration, for example, that the great majority of cargo containers are not scanned or physically inspected prior to arrival at a U.S. port. Similarly, some manufacturers have alleged that CBP has not adequately investigated allegations of duty evasion, product mislabeling, fraudulent country of origin declarations, or deliberate misclassification of shipments; and some assert that their intellectual property rights (IPR) are being violated by ever growing imports of counterfeit goods, and that CBP efforts in collaboration with the private sector in identifying and enforcing IPR violations have been inadequate. In short, how Congress and CBP balance trade facilitation, trade law enforcement, and import security has important implications for homeland security, public safety, and virtually every sector of the U.S. economy. To varying degrees, this tension underlies most aspects of U.S. import policymaking. Several bills have been introduced in the 114 th Congress to reauthorize CBP's customs-related activities, including S. 1269 , the Trade Facilitation and Trade Enforcement Act of 2015 (Hatch; introduced May 11, 2015); related bill H.R. 1907 (Tiberi; introduced April 21, 2015); and H.R. 1916 (Levin; introduced April 21, 2015).