University of Colorado will study the mechanisms that leads to computer science (CS) subfield segregation, knowledge that can be used to mitigate the lack of diversity in CS research subfields. The wide range of CS subfields is critical to nearly every other scientific endeavor, leading to strong and growing demand for CS research scientists. CS researchers do cutting edge, creative work, are placed into influential positions, and earn high salaries. Yet relatively few members of minoritized groups occupy CS research positions. Efforts to broaden participation in CS have focused on increasing numbers of historically minoritized group members in the broader discipline. However, evidence suggests that participation varies widely across CS subfields, with members of minoritized groups channeled into less prestigious and influential areas of specialization, positions, and roles. This "occupational segregation" jeopardizes U.S. innovation, economic competitiveness, and social justice. Studying the mechanisms that produce CS subfield segregation to mitigate lack of diversity in CS research subfields—in terms of both numbers and influence—has been neglected but is fundamental to the design of effective interventions in broadening participation in computing.<br/><br/>This Broadening Participation in Computing Demonstration Project aims to extend recent work on CS research subfield segregation by quantifying domestic racial and ethnic minority computer scientists by subfield and by developing a deep, qualitative understanding of how CS researchers come to choose subfields. A three-part, triangulated study is proposed: 1) in-depth interviews of computer scientists who are diverse in many ways (e.g., subfields, institutional types/roles, intersecting minority statuses, BPC involvement) will produce a qualitative understanding of the mechanisms behind CS research subfield choice; 2) textual analysis of public subfield discourse will make explicit the tacit values and beliefs about who belongs and who does not, as well as ways exclusion and inclusion are communicated; and 3) a large-scale survey will quantify participation of domestic racial minorities in CS subfields and may allow generalization and comparisons across groups of experience of the mechanisms revealed by the interview and textual analysis. The outcome will be a knowledge base that will better support development of interventions for overcoming CS subfield segregation<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.