More than five years after the adoption of the new labor regulations in Mexico (2017–2019), the purpose of this chapter is to offer a preliminary assessment of these historic transformations, with particular emphasis on trade unions and collective bargaining in the Mexican Automobile Industry (MAI). We argue that the results at this stage are mixed. Even though the new democratic institutions and procedures were established on time, violations of freedom of association and collective bargaining rights continue. However, some positive cases emerged quickly through the USMCA’s Rapid Response Labor Mechanism (RRLM) complaints procedure. These clearly exceptional results can be explained by the peremptory and coercive nature of the RRLM and considerable domestic and international solidarity, in contrast to the greater weakness displayed by the Mexican authorities in their ability to identify and sanction infringements of freedom of association and collective bargaining. To develop these ideas, we analyze the results of the process to legitimize the existing collective bargaining agreements (CBAs) as of 1 May 2019. Next, we examine the outcome of the 20 complaints filed by 15 December 2023 under the RRLM, most of which pertain to the MAI. In the third section, we examine official data and information from the Federal Center for Labor Conciliation and Registration’s new Labor Repository. Finally, we briefly examine how trade unions responded to the institutional changes by reviewing interviews with union leaders conducted two years after the reform.