Provisions on investment in the Comprehensive Economic and Trade Agreement (CETA) between Canada and the EU, both on substance and on dispute settlement procedures, are the culmination of a long process of replacement of the original EEC approach to establishment by the approaches followed by the GATS, the North American Free Trade Agreement (NAFTA) and Bilateral Investment Treaties (BITs). The article analyses this process; it focuses in particular on the law of external relations but takes into account the evolution of the law of the internal market and can also be read from this perspective as, in the authors’ opinion, the evolution in the former throws light on the latter. The article intends to leave the legal facts to speak by themselves. By unveiling their rationale, it also gives rise to political concerns regarding the evolution of the law. As CETA limits the ability of the EU to legislate and erodes the ECJ’s role, the article leads to the conclusion that the underlying rationale for the evolution, both in the internal and the external areas, has not been that of promoting integration but that of deregulation.