This study examined how vocational interests, vocational personal styles and work values impact on major satisfaction and specialization choice of 256 students in Master of Social Work programs from several regions of the United States. Participants completed the General Occupational Themes (GOTs) and the Personal Style Scales (PSSs) of the Strong Interest Inventory (SII; Donnay et al., 2005), the Values Scale (VS; Super & Nevill, 1989), and the modified Academic Major Satisfaction Scale (AMSS; Nauta, 2007). A series of logistic regression analyses were conducted to examine factors predicting major satisfaction, and a series of discriminant function analyses were conducted to investigate factors involved in distinguishing the three specialization groups (clinical social work-health/mental health/special population; clinical social work-children/youth/family; and non-profit organization administration/management, policy, community development). The results supported the importance of person-environment fit (P-E fit) in the membership of the MSW programs, the MSW students’ major satisfaction, and their specialization choices. The results also showed the validity and the utility of the GOTs, the PSSs, and the VS. Beyond three-letter Holland codes, further utilization of the GOTs and integration of the PSSs and the VS seem to be essential. Significant roles of work values of the VS were also noted. Implications for future research and career counseling are discussed. Recommendations for administrators of MSW programs are offered to more effectively recruit students, support their process of selecting a specialization, train them during the program, and provide additional training to professional social workers.