The adaptation finance gap is defined as the difference between the estimated costs of meeting a given adaptation target and the amount of finance available for adaptation (United Nations Environment Programme [UNEP] 2014). The AGR 2023 has undertaken a new and comprehensive analysis to estimate the adaptation finance gap for developing countries. Based on this analysis, this chapter compares the adaptation costs and finance needs against the current adaptation finance flows to estimate the size of the adaptation finance gap. It also considers the gender equality and social inclusion dimensions of adaptation costs, needs and finance. Finally, it discusses ways to potentially bridge the gap.