ABSTRACT Support is requested for a Keystone Symposia conference entitled Myeloid Cells: From Birth to Immunity and Disease, organized by Drs. Venizelos Papayannopoulos, Claudia Jakubzick and Martin Guilliams. The conference will be held in Banff, Alberta, Canada from March 6 - 9, 2022. Myeloid cells are the workhorses of the innate immune system. They are essential for survival and play central roles in human disease. Recent developments have uncovered novel roles for myeloid cells in orchestrating immune defense, tissue homeostasis, metabolic state, and neurological function. These functions are regulated by complex cellular signaling pathways and a fascinating network of interactions with other host cells and microbes and the microbiome. Myeloid cells can also be deregulated to promote inflammatory, metabolic, degenerative and neurological conditions and hijacked by pathogens and tumor cells to promote infection and cancer. The conference will explore the diverse biological roles of myeloid cells and highlight the pathways that define myeloid cell identity. One unique aspect of this conference is that one focus on the program will be on how myeloid cell differentiation is tuned by lifestyle, immunological and metabolic cues to shape cell function. The program will also cover the interactions between myeloid cells and other immune cells, tumors, the stroma and neuronal compartments. The conference will highlight the latest developments in our understanding of the cell biological, metabolic and signaling mechanisms that regulate myeloid cell responses. Attendees will leave the conference with a comprehensive view of how myeloid cell differentiation and cellular regulation impacts function in homeostasis and disease. This perspective will promote synergy across research areas and identify exciting future research directions.