A/HRC/25/53 scholars and activists to adopt the Maastricht Principles on Extraterritorial Obligations of States in the area of Economic, Social and Cultural Rights.61 The Special Rapporteur on the human right to safe drinking water and sanitation recently cited those Principles as underscoring “the obligation of States to avoid causing harm extraterritorially” and affirming “the obligation of States to protect human rights extraterritorially, i.e., to take necessary measures to ensure that non-State actors do not nullify or impair the enjoyment of economic, social and cultural rights. This translates into an obligation to avoid contamination of watercourses in other jurisdictions and to regulate non-State actors accordingly” (A/68/264, para. 46). 65. Such interpretations are in accord with the fundamental obligation of States to carry out their treaty commitments in good faith,62 which requires them to avoid taking actions calculated to frustrate the object and purpose of the treaty.63 The International Court of Justice has read this principle of pacta sunt servanda as requiring the parties to a treaty to apply it “in a reasonable way and in such a manner that its purpose can be realized”.64 This suggests that parties to a human rights treaty should not engage in conduct that makes it harder for other parties to fulfil their own obligations under the treaty.65 66. Other sources, such as the Special Representative of the Secretary-General on business and human rights, have taken a more restrictive view of the scope of extraterritorial human rights obligations. The Special Representative also stated, however, that “there is increasing encouragement at the international level… for home States to take regulatory action to prevent abuse by their companies overseas” (A/HRC/8/5, para. 19), and urged States to do more to prevent corporations from abusing human rights abroad (A/HRC/14/27). 67. Although work remains to be done to clarify the content of extraterritorial human rights obligations pertaining to the environment, the lack of complete clarity should not obscure a basic point: States have an obligation of international cooperation with respect to human rights, which is contained not only in treaties such as the International Covenant on Economic, Social and Cultural Rights (art. 2, para. 1), but also in the Charter of the United Nations itself (arts. 55 and 56). This obligation is of particular relevance to global environmental threats to human rights, such as climate change (A/HRC/10/61, para. 99). As the Human Rights Council noted in its resolution 16/11, principle 7 of the Rio Declaration states that “States shall cooperate in a spirit of global partnership to conserve, protect and restore the health and integrity of the Earth’s ecosystem.” 68. Indeed, much of international environmental law reflects efforts by States to cooperate in the face of transboundary and global challenges. Further work to clarify extraterritorial obligations in respect of environmental harm to human rights can receive guidance from international environmental instruments, many of which include specific provisions designed to identify and protect the rights of those affected by such harm.66 61 62 63 64 65 66 18 http://www.etoconsortium.org/nc/en/library/maastricht-principles/?tx_drblob_pi1%5Bdownload Uid%5D=23 Vienna Convention on the Law of Treaties, art. 26. Mark E. Villiger, Commentary on the 1969 Vienna Convention on the Law of Treaties (2009), p. 367. Case concerning the Gabcikovo-Nagymaros project (Hungary/Slovakia), 1997 International Court of Justice 7, para. 142. See Maastricht Principles, principle 20. See MEA report, sect. IV.A; and Aarhus report.