The Strategic Undergraduate STEM Talent Acceleration INitiative (SUSTAIN) provided a coherent ecosystem of academic, social, and career support services designed for a diverse cohort of high-achieving, low-income STEM students during their first year of undergraduate study. Findings are discussed in terms of the efficacy of the program interventions to enhance students' socialization and retention within the STEM community. Results indicate that participants perceived the interventions to have helped them adjust to college life and develop skills in understanding science and the scientific process. Which, in turn, participants reported, helped them to succeed in their STEM courses and visualize themselves as part of the larger STEM community. The participants rated STEM faculty mentoring, research experience, and community building as more helpful than other interventions. Our findings will aid researchers to better understand how SUSTAIN interventions influence students' socialization into the STEM community and provide valuable insight to guide policymakers in shaping future programs that are successful in retaining diverse students in STEM fields.