The Addis Ababa Action Agenda emphasizes the importance of infrastructure investment for achieving the SDGs. This will require a comprehensive approach, combining different financing modalities and instruments. It notes “that both public and private investment have key roles to play in infrastructure financing, including… mechanisms such as public-private partnerships.” Nonetheless, public-private partnerships (PPPs) have become fairly controversial in debates on implementation of the SDGs, with views ranging from the essential need for PPPs to achieve the agenda to fears that PPPs will be used to privatize public services and subsidize the private sector. The Addis Agenda recognizes these challenges, and notes that “careful consideration should be given to the appropriate structure and use of … blended finance, including PPPs, [and that projects] should share risks and reward fairly, include clear accountability mechanisms and meet social and environmental standards.”