This paper seeks to identify the voting cues used by state legislators when they are deciding how to vote on a specific roll call. It follows a research strategy suggested by John Kingdon's study of congressional voting decisions. The paper applies that strategy to the lower houses of three state legislatures: Massachusetts, New Hampshire, and Pennsylvania. The findings are that certain cue sources are consistently important (fellow legislators and interest groups) or consistently unimportant (the executive branch and personal reading) in all three legislatures, but other cue sources (party leadership, committee reports, and constituency) vary in importance quite substantially from one legislature to another. The data also suggest that some of these differences in the relative importance of cue sources may be related to differences in the level of legislative professionalization. Particularly interesting is the finding that the importance of constituents as a source of voting cues is highest in the least professionalized legislature.