Data centres in developing countries are set to grow rapidly due to economic expansion, rising data demand and increasing data sovereignty needs. However, these facilities are highly energy-intensive. Despite efficiency improvements, regulations remain insufficient, with the EU still drafting its first Data Centre Regulation. Against this background, United For Efficiency has developed the Sustainable Procurement Guidelines for Data Centres and Computer Servers. These guidelines are designed to help organisations set robust criteria and processes that improve the energy efficiency of their current or upcoming facilities. They offer recommendations on several key performance criteria and operating conditions that are most relevant and impactful for selecting energy-efficient data centres and computer servers. The criteria cover indicators such as power usage effectiveness, water usage effectiveness, IT equipment energy efficiency, and cooling effectiveness ratio.