A/HRC/25/19 and constraints and challenges. Several States also reported on recommendations that they had not initially supported during the previous review, a practice that should be encouraged. 90. Furthermore, the universality of coverage of the review mechanism has enabled or even strengthened the interaction with the United Nations human rights machinery of States that had relatively little experience in that regard. Pacific Island States addressing the Human Rights Council, shared their concerns and priorities, and contributed to raising awareness on issues that are not systematically part of the human rights debate, such as the impact of climate change on the enjoyment of human rights. 91. These various developments have confirmed and consolidated the universality of the universal periodic review process, which remains one of the main features of the United Nations and the establishment of the Human Rights Council. 92. OHCHR continued to prepare the documentation that informs the review debates and to support parties involved in the review. Requests to OHCHR to provide information, advice, technical cooperation and other forms of assistance in follow up on the review grew steadily, emanating from all regions. The two universal periodic review trust funds enabling States to prepare for and participate in the review, and to implement review outcomes,16 have been increasingly supported by donors and used by States and other stakeholders. 93. With the support of all Member States, the universal periodic review mechanism must face the challenge of following up on an increasing number of recommendations and ensure impact on the human rights situation on the ground. 5. Special procedures 94. As at November, 51 special procedures mandates were supported by OHCHR, including new mandates on the rights of older persons, the situation of human rights in Mali, and the Central African Republic. During the period under review, special procedures mandate holders conducted 75 country visits. The number of States that had issued standing invitations for special procedures rose to 94, although, regrettably they were not always honoured. As at November 2013, special procedures had issued 497 communications to 115 States, 81.9 per cent jointly by two or more mandates. The response rate to communications remained low, at 42.9 per cent. 95. Throughout the year, the special procedures continued their efforts to give a voice to victims and to ensure that civil society concerns are heard within the United Nations and by the broader public. The thematic and country expertise of the special procedures system helps to shed light on a wide range of human rights issues arising from new developments against a backdrop of international human rights law. Through that work, they complement my Office’s efforts under the various thematic priorities. I reiterate my call to all Member States to cooperate with the special procedures and to protect those cooperating with the United Nations system from an unacceptable exposure to acts of reprisal. 96. OHCHR continued to lend full support to special procedures mandate holders, including by contributing to research and reports, and visits and consultations. It also continued to encourage and support greater coordination and harmonization of working methods among special procedures mandates, including through the Coordinating Committee. 97. A total of 27 special procedures mandate holders will be appointed in 2014; it is critical to ensure the quality of the selected candidates in accordance with the procedures and criteria established by the Human Rights Council. 16 See A/HRC/24/56. 17