S. Rept. 116-283: United States-Mexico-Canada Agreement Implementation Act, Report Together with Additional Views, to Accompany H.R. 5430, Including Cost Estimate of the Congressional Budget Office, October 21, 2020 [open pdf - 2MB]
From the Background: "On February 2, 2017, President Trump announced his intention to renegotiate the North American Free Trade Agreement (NAFTA). President Trump had made redressing NAFTA's short-comings one of his top priorities upon entering into office. In accordance with Section 105(a)(1) of the Bipartisan Congressional Trade Priorities and Accountability Act of 2015 (TPA 2015) (Pub. L. 114-26), U.S. Trade Representative Robert E. Lighthizer notified Congress on May 18, 2017 that the President intended to initiate negotiations with Canada and the United Mexican States (Mexico) regarding modernizing NAFTA. In his letter, Ambassador Lighthizer noted that: . . . NAFTA was negotiated 25 years ago, and while our economy and businesses have changed considerably over that period, NAFTA has not. Many chapters are outdated and do not reflect modern standards."
S. Rept. 116-283; Senate Report 116-283
U.S. Government Publishing Office: http://www.gpo.gov/