We report on our findings regarding authors' use of theory in 1,160 articles that appeared in six information science (IS) journals from 1993–1998. Our findings indicate that theory was discussed in 34.1% of the articles (0.93 theory incidents per article; 2.73 incidents per article when considering only those articles employing theory). The majority of these theories were from the social sciences (45.4%), followed by IS (29.9%), the sciences (19.3%), and humanities (5.4%). New IS theories were proposed by 71 authors. When compared with previous studies, our results suggest an increase in the use of theory within IS. However, clear discrepancies were evident in terms of how researchers working in different subfields define theory. Results from citation analysis indicate that IS theory is not heavily cited outside the field, except by IS authors publishing in other literatures. Suggestions for further research are discussed.