This is the first article evaluating the concurrent validity of the 2005 Strong Interest Inventory (SII). The Basic Interest Scales (BISs) were substantially revised to reflect the changing workplace, so such an update is particularly important. Concurrent validity of the 41 content scales in the SII was examined for differentiating 31 college majors in a national college sample of 1,403 women and 469 men. Using discriminant analyses, three sets of content scales were used to predict major field of study. These were six General Occupational Scales, five Personal Style Scales, and 30 BISs. Each set of scales showed substantial concurrent validity in differentiating college major for women and men. The most specific scales, the BISs, were the most predictive of major, with hit rates 6 times greater than chance. Results clearly supported the concurrent validity and counseling utility of the content scales of the SII. (Contains 4 tables, 5 figures, and 2 endnotes.)