Background/Context: The subject of this study concerns the Michigan College Access Network (MCAN), a college access program that has operated in Michigan since 2010 to promote postsecondary access and equity statewide. The state of Michigan has trailed nationally in educational quality and attainment for the past several decades, ranking 38th in public education quality (US News, 2022) and 35th in postsecondary educational attainment (PSEA) (Lumina Foundation, 2022). To address Michigan's lag in the latter, MCAN was created in 2010 to also mitigate the state's drastic 30% decline in public education funding since 2002 (MSU Today, 2019). This organization's goal and motto is "Sixty by 30", which means increase the PSEA of the state to 60% by 2030. MCAN hosts AdviseMI and Michigan State University College Advising Corps (MSUCAC) under the greater national umbrella of AmeriCorps. These programs recruit college graduates to serve as college advisors in high schools across Michigan. Both AdviseMI and MSUCAC are funded via a five-pronged cooperation between the federal government, state government, philanthropy, participating universities, and schools involved. College advisors are expected to meet with students individually and in groups, give presentations to classes about key targets, plan events such as: college fairs, scholarship/application nights, and much more. The extreme variability of a college advisor's duties makes these programs flexible and receptive to each individual school across Michigan. During the 2021-2022 academic year, MCAN's programs were serving 112 schools with 91 advisors. Purpose/Objective/Research Question: This paper approaches MCAN from a perspective much aligned with the stated goals of MCAN itself, that is, postsecondary equity through increased, targeted counseling and advising at the high school level. Building a more equitable postsecondary system involves work at every stage of one's K-12 education into postsecondary. MCAN targets the "access" portion of the process by helping high schoolers plan, get into, and enroll in a postsecondary institution, hence the "access" in MCAN and CAC. From this we ask: does having a college advisor increase PSE and PSEA at designated high schools? Setting: [See background and data collection sections]. Population/Participants/Subjects: [See background and intervention sections.] Intervention/Program/Practice: MCAN uses a competitive, grant-based approach by targeting high schools across Michigan with several qualifying factors: postsecondary enrollment (PSE) rate below the state average, free- and reduced-lunch rate above the state average, and a large percentage of "target populations" such as: low-income, first-generation, and students from underrepresented, minoritized populations. Schools that qualify are invited to apply for the grant and recipients are provided a college advisor; a recent college graduate and AmeriCorps service member trained by MCAN to promote PSE among the student population. Implementation of promotion is highly variable, but the following are key targets: (1) College awareness; (2)FAFSA completion; (3) College applications; (4) Scholarship applications; (5) Financial literacy; (6) Postsecondary navigation. Research Design: We test the effect of the Michigan College Access Network (MCAN) on postsecondary enrollment (PSE) in Michigan since MCAN's inception in 2010. Using public, student-level data from the Michigan Education Research Institute in combination with school-level data provided by MCAN, we apply staggered difference-in-differences (DD) statistical methods (Callaway & Sant'Anna, 2021; Goodman-Bacon, 2021) to analyze the effects on PSE upon receiving a grant from MCAN. To specify our control and treatment groups, we use MCAN's data showing which schools have had an advisor (treatment), and which schools qualify, but have not received an advisor (control). We also apply weights to our sample populations to ensure that our demographics balance as the control group is more likely to be attending an urban school district and be Black or Latino. More recently, some schools have not renewed their grants and some have gone in and out of the program, necessitating advanced staggered DD methods to account for different treatment periods and dropoffs. Schools leaving the program may complicate results as well as potential selection bias and parallel trends, which are concepts also covered in detail. Data Collection and Analysis: The data consist of all the schools partnered with AdviseMI and MSUCAC since they began and schools that fit the criteria to qualify for the grant as of the 2021-2022 academic year. The time period for our data runs from the academic years 2007-08 to 2021-2022, over one decade of data starting well before the first schools partnered with MSUCAC in 2011 and AdviseMI in 2015. Among the 279 high schools throughout Michigan that qualify for the grant, there are 112 schools that have had a college advisor (treatment group) with the remaining 167 schools qualifying for but never receiving the grant (control). The main outcome we intend to focus on is PSE of all 279 high schools using a DD model. The data contain general information on all public schools throughout Michigan including senior enrollment count, graduation rate, PSE rate, race, gender, urban/rural location, program affiliation, and years that schools had a college advisor. Findings/Results: Preliminary results show that MCAN's programs have had a significant, positive impact on PSE rates of schools with large populations of students from underrepresented groups. Schools receiving the grant see an average increase of 2.9 percentage points in PSE among their senior body, and 3.8 percentage points for high school graduates. Regarding boosting PSE, having someone present in a disadvantaged high school whose job is to promote PSEA appears effective under the AdviseMI and MSUCAC programs. Conclusions: Findings from this paper indicate that increased advising and counseling on postsecondary education may lead to increased PSE. Contributions to the literature of postsecondary access and advising include an external analysis of a state-based AmeriCorps program using DD methods and reaffirms the importance of guidance and understanding when navigating the higher education process, and more equitably improving the postsecondary system.