This paper is the first in Pioneer Institute's UMass at a Crossroads series. In the opening study, the authors focus on UMass' significant growth in two areas, academic competitiveness and student enrollment, compared to other New England state universities, MA private universities, national private universities and national public universities. UMass has expanded enrollment more rapidly than other comparable university systems in the last ten years. As this paper will illustrate, UMass' enrollment expansion has continued against the backdrop of a projected decline in high school graduates in Massachusetts. The Western Interstate Commission for Higher Education (WICHE) forecasts that the number of high school graduates will decline by 11.4 percent from 2015-16 to 2027-28. In spite of these projections, the school has continued to grow its enrollment and expand its capital facilities to historic levels. Through the past decade of enormous growth in enrollment, the university has significantly elevated its academic profile. This is evidenced by its rise in rankings--in just five years UMass Amherst, UMass' flagship campus, rose more than 20 in rank in the top 100 of U.S. News and World Report's 2014 rankings of national universities. UMass' rising academic rank and its growing national profile have led to increasingly competitive admissions, which has made it considerably more difficult for Massachusetts students to be admitted. One of the most significant contributing factors to this trend has been the university's admittance of a growing percentage of out-of-state and international students in recent years. While UMass has been accepting significantly higher volumes of out-of-state students relative to in-state enrollees, the school's enormous growth is also reflective of its growing popularity as a higher education option for in-state students. Pioneer raises the question of whether the continued expansion of UMass, based largely on increased enrollment of out-of-state students, is in the best interest of the commonwealth. With a comprehensive examination of trends in enrollment, Pioneer's aim is to illustrate the degree to which UMass' changing priorities in recruitment present a number of a grave concerns for in-state students and Massachusetts residents at-large. UMass is fundamentally changing, and this evaluation of the trends of the last ten years is part of a larger discussion about how the university can best serve the commonwealth while maintaining a sustainable fiscal course. [For "UMass at a Crossroads Part 2: Is UMass' Expansion Fiscally Sustainable? White Paper No. 146," see ED598659. For "UMass at a Crossroads Part 3: UMass' Growing Dependency on Tuition and Fees and Strategic Recruitment of Out-of-State Students. White Paper No. 147," see ED598661.]