Support is requested for a Keystone Symposia meeting entitled Stem Cells and Cancer, organized by Tannishtha Reya, Craig T. Jordan and Philip A. Beachy. The meeting will be held in Banff, Alberta, Canada from February 2-7, 2014. This meeting will bring together leaders in cancer research with the overall goal of defining new pathways and mechanisms that drive oncogenesis and that may be targeted in therapy. In particular, the meeting will examine the links between stem cell development and cancer initiation and progression: how signals active during stem cell development may be reactivated in cancer growth and relapse, the importance of the cell of origin for cancer initiation, and the role of cancer stem cells in cancer propagation. The conference will also address how cancers grow and invade the surrounding microenvironment by highlighting work on in vivo imaging and metastasis. A major objective of the meeting will be to consider these issues in context of translation; key panels will discuss development of better preclinical models of cancer and designing more effective strategies to move basic discoveries to the clinic. Opportunities for interdisciplinary interactions will be significantly enhanced by the concurrent meeting on Developmental Pathways and Cancer: Wnt, Notch and Hedgehog, which will share keynote addresses and a plenary session with this meeting. Thus, the program for this meeting is highly likely to attract a wide variety of investigators, many of whom might not otherwise interact.