Higher education administrators recognize the importance of examining persistence as a means of understanding why students and have significant variability in enrollment patterns and depart from college prematurely (Braxton, 2000). One of the most common methods of evaluating student persistence is through academic achievement, measured by grade point average (McGrath & Braunstein, 1997; Tross, Harper, Osher, & Kneidinger, 2000). Previous researchers indicate academic achievement of college students can be influenced by a number of factors including academic major (Turner & Bowen, 1999). One group that has not received significant attention by researchers is the undecided population, those students who matriculate to colleges and universities without declaring an academic major. Undecided students warrant additional research as they make up one of the fastest growing populations in higher education. Anywhere from 20% to 50% of entering college students are undecided majors (Lewallen, 1995). These students are often described as a vulnerable group with a decreased probability of persisting. The purpose of the current study was to explore differences between two sub-groups of undecided students. In addition, an investigation was conducted into which factors could predict the academic achievement of first year, undecided students. Undecided students were classified as either Non-Specific Majors (NSMs, students who indicated they were not able or did not want to make a commitment to one particular major at the time they applied for admission to the university) or Specific Majors (SMs, students who indicated a particular degree granting program as their first choice of major but were not accepted to that major). Background characteristics, self-perception of abilities, degree aspirations, and academic achievement were examined using secondary analysis of institutional Cooperative Institutional Research Program (CIRP) data. Findings revealed significant differences between NSMs and SMs. In terms of their background characteristics, four significant differences were identified including sex, high school grade point average, race, and parental education. Only one measure of self-perception of abilities revealed a significant difference between the two groups: artistic abilities. No significant differences were found in terms of degree aspirations. Regarding academic achievement, NSMs tended to experience higher levels of academic success than SMs. Finally, for both the NSM and SM group, background characteristics, self-perceptions of abilities, and degree aspirations were able to explain a significant amount in variance in academic achievement, though to a greater degree within the NSM group. / Ph. D.