The authors use an informational-theoretical perspective to examine the appointment of legislative committees, using new measures of knowledge and expertise as well as a unique database. While competing theories (distributive and partisan) do not deny that legislative committees are a source of vital knowledge and expertise necessary for legislative policy making, information theory places the wisdom and expertise needs of collective decision making—that is, specialization—on very complex topics by legislative generalists as the raison d'être for a committee system. Thus, the authors investigate one of the fundamental arguments of information theory—that committees are formed to meet the basic knowledge and expertise needs of a legislative body. The findings from U.S. state legislative data indicate that significant member differences regarding prior knowledge and expertise exist by committee jurisdiction, state, and session, reinforcing the applicability of information theory while also suggesting the impact of setting and organizational factors. The authors also explore implications of these findings.