PROJECT SUMMARY We request funds to support the 24th Gordon Research Conference (GRC) on Fertilization and Activation of Development. The GRC will integrate research across approaches including genetic, physiological, biochemical/biophysical, molecular/cellular, imaging, evolutionary, and organismal, and across a range of organisms. Thus, the GRC will reveal conserved mechanisms of fertilization and ways that these mechanisms can be modified. The topics covered in this GRC are of both fundamental and applied importance in biology and biomedical research. This is supported by the award of the 2010 Nobel Prize for in vitro fertilization and the 2012 Nobel Prize for induced pluripotent stem cells. In fact, a leader in converting induced pluripotent stem cells into gametes spoke at the 2015 GRC. This GRC is the only meeting worldwide focused specifically on fertilization biology. In recent years, researchers in this field have identified molecules that mediate sperm-egg recognition and fusion, defined the roles of the reproductive tract and its products such as exosomes in supporting fertilization, and identified mechanisms that activate fertilized eggs to transition to embryogenesis. This year, the Keynote speaker will be developmental and cell biologist Dr. Ruth Lehmann. Her lab has used Drosophila to shed light on how germline stem cells become germ cells and how they travel from where they originate to the gonad during early embryonic development. The 2021 GRC will include topics that were not discussed in previous GRCs such as new targets and mechanisms that can be targeted for male or female contraception, aspects of viral–cell fusion that pertain to sperm–egg fusion, and environmental effects on reproductive mechanisms and behavior. The GRC will be immediately preceded by a Gordon Research Seminar, which attracts and scientifically nurtures young investigators in the field of gamete research and fertilization. New this year will be a mentorship event at which panelists will discuss a variety of career opportunities after completing a PhD program. The panel will comprise three academically trained scientists who took different career pathways (Ushma Neill, Vice President of Scientific Education and Training at Memorial Sloan Kettering; Nancy Ryan Gray, Gordon Research Conferences director; and Mariana Wolfner, Goldwin Smith Professor of Molecular Biology and Genetics at Cornell University). This GRC has a long tradition of creating a forum for presenting and discussing cutting-edge research and fostering a vibrant atmosphere to facilitate scientific interactions. Thus, this GRC will advance and “cross- fertilize” the science and provide a supportive environment for both established and new investigators. An important goal of this GRC is to foster and encourage inclusion and participation by members of groups traditionally underrepresented in the sciences, including women, minorities, and people with disabilities.