ABSTRACT Support is requested for a Keystone Symposia conference entitled Metastasis, organized by Drs. Joan Massagué, Sean Morrison and Caroline Dive. The conference will be held in Vancouver, British Columbia Canada from May 7- 10, 2023. Most cancer deaths are caused by distant metastasis, yet the mechanisms that regulate distant metastasis are poorly understood. Metastasis is a very inefficient process in which few disseminated cancer cells survive, and even fewer proliferate, but little is known about why. This conference will address the nature of metastasis initiating cells as well as their phenotypic plasticity, genetic and epigenetic evolution. Speakers will cover topics including the characterization of circulating cancer cells and how recent advances in imaging and DNA analysis are assisting the clinical management of metastasis. Other sessions will cover why cancer cells sometimes go dormant after metastasis. Additionally, the program will include sessions which will discuss the metabolic regulation of metastasis and how the metabolic environment influences the survival of cancer cells during metastasis. Finally, this conference is being paired with the Keystone Symposia conference entitled, The Resistant Tumor Microenvironment. There will be joint sessions and attendees of both conferences will be able to interact and network during mealtimes and poster sessions.