The Scenarios and Interpretive Science Coordinating Group (SISCG) is an interagency coordinating group, supporting the U.S. Global Change Research Program (USGCRP). The SISCG convened the Towards Scenarios of U.S. Demographic Change Workshop in Rockville, Maryland on June 23 and 24, 2014 to assess key factors in the development of long-term population and demographic scenarios for use in interdisciplinary social and environmental applications, with a strong focus on climate change. The workshop brought together 52 experts from federal and state agencies, non-governmental organizations (NGOs), and research institutions with backgrounds in climate change scenarios, environmental change, demographics, and human health. Over the course of two days, participants explored the needs of the user communities and the capabilities of the modeling community to meet these needs, and identified next steps. This workshop report synthesizes the presentations and discussions held during the workshop (as well as background materials and webinars held in advance of the workshop). The sections below briefly summarize the report, paralleling its organization.