Background: Research shows that serving as an assistant principal is a typical steppingstone to the principalship (Folsom et al., 2015; Goldring et al., 2021; Hitt & Player, 2019; Osborne-Lampkin & Folsom, 2017) and assistant principals serve important leadership roles in schools, supporting principals and teachers (Marshall & Hooley, 2006). However, research also suggests that job assignment and career advancement for APs of color and women differs from their peers (Bartanen et al., 2021; Moyer & Goldring, 2023). The assistant principal role thus has implications for equity, both in terms of diversifying the principal pipeline (Crawford & Fuller, 2017; Fuller et al., 2016, 2019) and supporting diverse populations of students (Bottiani et al., 2017; Welsh & Little, 2018). This paper draws from an in-depth, mixed-methods case study of a large, diverse urban school district to examine the assistant principalship and describe racial and gender differences. It seeks to build the knowledge base about how the AP position can serve as a steppingstone to increase diversity in the principalship and to advance educational equity. Research Questions: 1. How have the number, distribution, and demographic characteristics of APs changed over time? 2. How does career advancement into the AP role differ by educators' race and gender? 3. What is the relationship between APs' demographic characteristics and the student populations they serve? Setting: The setting for this study is a large, urban district in the southeastern United States. District enrollment is more than 150,000 students in about 200 schools across a large, diverse geographic area. The district is majority non-White with approximately 20% of students eligible for free and reduced-price lunch. Enrollment increased by ~10,000 students in the past decade. District governance is divided among regional leaders who exercise a high-level of autonomy. Participants: The quantitative analyses include longitudinal administrative data from the 2011-12 through 2021-22 school years for all educators (teachers, assistant principals, and principals) in the district. We conducted in-person and virtual interviews from December 2023 to February 2024 with five central office staff, seven principals, and eight assistant principals. We selected leaders through district recommendations and snowballing to gather diverse perspectives from across school levels, contexts, and experiences. Analyses: Using administrative data, we describe the career paths of assistant principals, including racial and gender differences. We use descriptive statistics to examine the distribution of assistant principals across schools in the district; the racial and ethnic diversity of teachers, assistant principals, and principals; and the characteristics of schools served by APs of different races and genders. We conduct survival analyses (Cox proportional hazard models) to compare the rates that educators of different races and genders advanced to AP or principal positions. We examine different samples and career advancement outcomes. Qualitative data were collected through hour-long semi-structured interviews. Central office staff interviews focused on district policies for AP hiring, training, career paths, allocation, role assignment, and diversity goals. The AP and principal protocols asked about individual experiences regarding career progression, diversity, mentorship, and evaluation. Recordings and transcripts of these interviews were coded and analyzed. Findings: The number of APs increased substantially in the district from 2012 to 2022. The growth rate for APs (47 percent) exceeded those for principals and teachers (13 and 16 percent) as well as students (8 percent). Leaders explained that AP positions increased due to changes in district policy made in response to concerns about school safety and management. Interviewees shared that allocating more APs allowed schools to be "well managed" with "visible" adults throughout the building. School leaders perceived that APs help develop relationships with students to better address conflicts, support students social, and to protect the principal's time. "It's a supervision and safety issue; for a long-time middle school only had one AP, then we were basing assistant principal allotment on the state ADM (average daily membership). Now with the number of safety and supervision concerns the district pays for a lot of additional APs through the local budget." -- central office leader. Black male educators comprised a small share of educators with a school leader certificate, but those with a certificate had a greater likelihood of becoming an assistant principal. Five years after receiving their certificate, 73 percent of Black men were APs, compared with 46 percent of White men, 33 percent of Black women, and 25 percent of White women. Black APs served schools with higher percentages of students of color. When leaders of color discussed job seeking strategies, race was a reoccurring theme. Some leaders noted they would not be welcomed in certain schools, others explained that they wanted to serve schools with Black and Brown students or were more likely to be hired in those schools. Some interviewees suggested that leaders of color were likely steered to schools that served students of color and away from schools serving majority white populations. "If someone of color is at a school that is predominantly white, it can be more challenging. And it could be because parents don't want them there. [Parents will] go to the school board, or they just make it very challenging for someone of color to even feel wanted--they will constantly complain. Or anything that a change that's made, they're against it." -- high school AP. APs and principals also expressed that there is a common perception that leaders of color can better meet the needs of students of color; in addition to personal preferences, steering is perceived to contribute to the number of Black APs in these schools. Conclusions: As one of the most visible leadership roles in the district, there are important implications for who occupies the AP position for diversity and equity. We find that experiences with career progression and assignment differ by race and gender. Our qualitative findings suggest that differential placement is a combination of self-selection and implicit steering practices. The paper discusses implications of these finding to inform district polices on leadership pipelines.