The AACR, in conjunction with the Tumor Microenvironment (TME) Working Group, is proud to present this special conference devoted solely to the tumor microenvironment. This conference provides a fresh glimpse into how aspects of tumor microenvironments regulate cancer initiation and progression through interactions between initiated cells, activated stromal cells and components of the extracellular matrix. Sessions cover significant findings in basic science and the therapeutic opportunities revealed by these new discoveries. Dr. Luis Parada of UT Southwestern Medical Center at Dallas will commence this conference with an opening keynote address and Dr. Michael Karin of University of California, San Diego, will present the closing keynote address. This conference also features an NCI Workshop, Tumor Microenvironment Network (TMEN): Goals and Objectives presented by Dr. Suresh Mohla. Poster sessions and proffered talks from selected abstracts are scheduled to allow investigators to present and discuss their latest research.