Design experiences offer opportunities for students to develop a wide range of technical and professional skills. Community-engagement or service-learning is becoming more pervasive in engineering and offers opportunities for students to engage in designs that address human, community and environmental needs. Connecting engineering with these areas is cited in the literature as a means to potentially enhance diversity and retention. Analyses in this paper indeed show a positive impact on the retention of students who engage in the EPICS Program early in their academic program and female students in particular. Furthermore, there are many benefits of extended design experiences and the data shows that participation over multiple semesters has a significant impact on the depth of the experiences. In addition to the personal benefits, the participation of students over multiple years also offers opportunities for mentoring younger students within the course and can further impact the diversity and retention efforts.