Expected Library of Congress Subject Headings (LCSHs) and assigned LCSHs for 161 books requested by faculty in sociology, anthropology, and social work were compared to gauge the likely success of an online subject catalog search for those works. For 80% of the titles checked, inspection of the ninth edition of "Library of Congress Subject Headings" resulted in successful access. Subject searching was more effective for social work titles than for works in anthropology or sociology. Analysis of the comparisons expected with actual LCSHs revealed three types of subject access problems that could be addressed in online catalogs with the use of keyword-in-title, combinatorial, and cross-referenced features. The data also showed that shelf browsing in these three social science fields would not be a systematic or reliable way in which to locate desired books. (There are 14 references.) (Author/EW)