The Habitat III Issue Papers are summary documents that address research areas, highlight general findings, and identify research needs on topics related to housing and sustainable urban development. Through its Task Team on Habitat III, the United Nations system collaborated on the preparation of the Issue Papers. The Papers provided a background on each thematic area as well as the key challenges and recommended next steps. These were vital documents in the Habitat III process, having established in-depth review and analysis on specific relevant issues, and ultimately serving as the foundation for the work of the Policy Units.