Educational Opportunity Program (EOP), Summer Bridge Programs (SBP)across the California State University (CSU) system vary in design and delivery. This mixed-methods study investigated six CSU SBP designs, delivery, and 4-year graduation rates of SBP participants during the 2015 through 2019 years. The qualitative portion of this study consisted of interviews with six SBP Coordinators across various CSUs and discovered major themes and subthemes. Themes uncovered in the semi-structured interviews were: a) SBP effectiveness, subtheme of pre and post surveys; b) program changes, sub themes of student recommendations, improvements, identification of what is/is not working, engagement, and budget restraints; c) student backgrounds, subthemes of student cultures, familial expectations, first generation college student, equity and accessibility; d) measurement of student success; subthemes of data, assessments, retention and graduation; e) SBP design, subthemes of academic advising, transition, workshops, collaboration, faculty-student interaction, college experience, campus resources, academic classes, and non-academic activities; f) support, subtheme of student help/assistance; g) student expectations, subthemes of realistic expectations, and college-level expectations; and f)relationships/community, subthemes of student-centered decision making, communication, understanding, sense of belonging, and honesty. The second qualitative portion of this study consisted of a document review analysis which indicated major and subthemes. Themes were: a) SBP structure; subthemes of length of SBP, mandatory attendance, commuter/residential/virtual-based program, college courses, and workshops; b) SBP content, subthemes of college courses and workshops; and c) SBP mission/vision, subthemes of EOP community, transition, college readiness, meet requirements, cultural/social exposure. The third portion of the study was quantitative in design, and investigated six CSUs 4-year graduation rates, of EOP participants, SBP participants, and non-EOP/SBP participants. Findings indicated that four out of the six CSUs, non-EOP participants graduated at higher rates than EOP/SBP participants, and two out of four CSUs SBP participants had higher 4-year graduation rates then non-SBP participants. This study concluded that more research should be conducted on CSU SBPs, and suggested that a SBP evaluation model should be implemented in order to build best practices and maintain fluidity of programmatic quality. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]