The Basic Interest Scales (BISs) of the Strong Interest Inventory (SII; Harmon, Hansen, Borgen, & Hammer, 1994) have a 35-year history. The BISs are the specific content scales of the SII, as opposed to the SII general content scales, the General Occupational Themes (GOTs), which measure the six Holland (1997) RIASEC themes. Using 17,074 participants from the 1994 SII national norm group who majored in 24 different areas, this study examined the incremental value of the specific BISs over the general GOTs in explaining major field of education or training. Multivariately, discriminant function analyses were used to compare the ability of the set of the six GOTs and the set of the 25 BISs to predict the 24 major fields. Results showed substantial increases in explanatory power when the BISs were added to the GOTs. For 22 of the 24 fields, the addition of BISs to the GOTs added significantly to prediction of the major. These results showed that specific interest scales, such as the BISs, are highly useful in explaining specific criteria, such as choice of major field of education or training.