Since the Me Too Movement sparked national awareness of sexual harassment in 2017, many industries are learning of harassment issues that had been ignored for a long time. Science, technology, engineering, and medicine (STEM) fields often share characteristics that create risk factors for harassment, which can lead to a loss of valuable talent and a persistent gender gap in fields that are increasingly important to our future. With support from the Rockefeller Family Fund, on October 30, 2019, the American Geophysical Union, in partnership with the Urban Institute and the National Women’s Law Center, hosted a convening on best practices to address sexual harassment in STEM workplaces. Although many organizations promote training and education to encourage women and people of color to enter STEM fields, participants agreed that STEM employers need to do more to share knowledge and evidence on what works to prevent harassment to create work environments where workers from underrepresented backgrounds can thrive. The panels and discussions throughout the day focused on how institutions can create stronger practices and organizational climates that do not tolerate harassment. Although the research is still evolving on what truly works as a “best practice” to end harassment, many organizations have been experimenting with new and innovative practices to shift culture and change behavior. This report highlights five promising practices and key takeaways coming out of the convening discussion to help organizations create a culture where harassment is not tolerated, and concludes with three recommendations for next steps.