Job outsourcing, as a phenomenon that became increasingly widespread and complex since the 1970s when the worldwide process of capitalist restructuring began, has also affected Latin American countries. The article seeks to contribute to a more complex analysis of job outsourcing, on the basis of the following questions: What are the objectives of companies that resort to outsourcing? How does it affect the lives of workers and their organizations? What policies are unions adopting in view of job outsourcing? In order to carry out this study, we selected a qualitative case methodology as the most pertinent to carry out an in-depth and complex analysis of the phenomenon. The case analyzed is that of outsourcing in the Argentinean electricity sector between 1992 and 2016, specifically that of the workers of the main power companies based in the Federal Capital and the Province of Buenos Aires and of the Luz y Fuerza Capital Federal (LyF CF) union. The article addresses three main themes. First of all, it makes some conceptual clarifications, showing how job outsourcing takes on different legal forms and how it pursues three types of objectives: techno-efficiency-based, economic, and political objectives. Secondly, it presents the case study, which describes the outsourcing process in the electricity sector, inquires into the possible objectives it seeks, and explains its effects on the electricity sector workers and the lyf cf union, on the one hand. On the other hand, it analyzes the policy adopted by the trade union in view of this process and identifies some of the actions it took in that respect. One of the conclusions of the research project is that although there are many theoretical studies on the causes that lead businesses to outsourcing, it is necessary to carry out more complex analyses of the issue through access to more and better research resources. The article also concludes that outsourcing entails a fragmentation and weakening of workers’ rights and of their union organization, which, as an active subject, can adopt different support or opposition policies.