The development of the ‘duty to regulate’ paradigm in the present study is an attempt to revisit the long-standing critical stand of Latin American countries towards international legal instruments protecting foreign investment and steer it towards the contentious issues which, from a human rights law perspective, should be addressed. By using Latin America as a case example, this monograph invites international investment law (IIL) scholars to integrate international human rights law (IHRL) in their analysis. These legal standards not only indisputably apply to states in the investment context, but also normatively inform foreign investors’ responsbilities throughout the undertaking of their economic activities in these countries. Concerning human rights scholars, this work provides a normative tool to frame the issues of contention regarding the IIL regime’s operation and to articulate their views in a way that IIL is familiar with while consistent with IHRL.