Since 1974 the United States Congress has enacted several Trade Promotion Authority (TPA) acts to ensure speedy ratification of trade agreements in the United States, while maintaining a congressional hold on the objectives to be pursued by US negotiators. TPA defines the conditions and procedures for using a streamlined or expedited procedure, also known as the fast-track procedure, to vote in Congress on international trade agreements negotiated during a specific defined period of time. The current (2015) Trade Promotion Authority Act, which was finally passed in June 2015, sets out the rules for the expedited procedures applicable to any international agreement entered into by the US before 1 July 2018 (with possible extension up to 1 July 2021), covering inter alia the recently concluded Trans-Pacific Partnership and any agreement stemming from the ongoing Transatlantic Trade and Investment Partnership negotiations. The TPA requirements in terms of negotiating objectives and consultation have constantly evolved to match the rising political need of Congress to exert greater control over the outcomes of US trade negotiations.