This article is a pre-conference paper prepared for participants at AACRAO's Fifteenth Annual Strategic Enrollment Management Conference (SEM XV), held November 13-16, 2005, in Chicago, Illinois. This is the first of a three-part series. In this series of papers, David Kalsbeek introduces a four-fold construct for differentiating and comparing institutional approaches to SEM, four broad but distinct orientations that characterize how SEM structures and strategies are designed in colleges and universities. The four orientations that characterize EM structures include: (1) Administrative orientation; (2) Student-focused orientation; (3) Academic orientation; and (4) Market-centered orientation. (Contains 1 figure.) [For "Some Reflections on SEM Structures and Strategies. Part Two," see EJ745911.]