This study was conducted because limited research has occurred in the area of co-curricular student learning outcomes assessment, which has resulted in confusion within the student affairs profession on how to develop and implement assessment plans. The purpose of this study was to examine high-quality assessment practices of student affairs divisions at three different research institutions in order to advance the value, usefulness, and understanding of learning outcomes assessment within the student affairs profession, so more student affairs divisions may begin assessing the co-curricular. Those student affairs divisions selected for this study represented assessment models with significant experience in successfully implementing assessments of student learning and development. These mature student affairs divisions who have substantial experience in successfully implementing their assessment plans were important to examine closely so that others can learn from their experiences. This study found that those student affairs divisions that participated in this study fostered a shared commitment to assessment. It became apparent that there are four levels of professional commitment to each student affairs division's assessment initiative. Those four levels of professional commitment included: vice presidents, directors/coordinators of assessment, assessment committees, and unit-level professional staff. This research clearly indicates that successful assessment of student affairs learning outcomes requires the understanding that units are experts in their particular field; therefore, a decentralized model of assessment, facilitated by a coordinator or director, is most appropriate in student affairs. This study also explores the most commonly used assessment methods in student affairs, as well as student affairs efforts to collaborate in the assessment process. Moreover, this study investigates how student learning outcomes assessment results are used to enhance the student co-curricular experience. Finally, this study highlights the assessment successes and challenges identified by each of the three institutions that participated in this study. (Contains 1 figure and 2 tables.)