users invoked: how documents help readers assume user roles  a typical and often productive response to writing for documentation audiences is to think in terms of types or genres of documentation---reference manuals, tutorials, "using" manuals, quick reference books and cards, and so on. these categories can help writers think about readers, at least the general purposes for which readers consult documentation.  unfortunately these forms of documentation say little about the many local decisions computer users make as they read documentation. sticht (1985), diehl and mikulecky (1981) and others have described how readers may read to do specific tasks or read to learn material. sullivan and flower (1986) show that users may not read a manual or section of a manual in its entirety, and that when they do read, they read to answer questions that arise during a task. the implication of this research is that users' purposes for reading are likely to vary and that these purposes may be determined by work-related tasks or problems which occur during the tasks.  a question arises, however, about the role of texts in influencing how readers read computer manuals. if readers' purposes for reading come from outside text ---a task or problem stemming from a task---do the text themselves influence the readers? rhetorical theory suggests one answer: that cues in texts invoke reader roles which readers take on as they read.  the theory comes to rhetoric by way of literary criticism and rhetoric. gibson (1949-50), for instance, argues that tests imply a "mock reader," an entity distinct from the real reader, by marshaling semantic and syntactic cues in a text. the rhetorician walter ong (1977) develops this idea further; he explains that the mock or fictionalized reader is actually a role created in the text and that the notion of reader roles is relevant to all writing, not just fictional writing: the "historian, the scholar or scientist, and the simple letter writer all fictionalize their audiences, casting them in a make- up role and calling on them to play the role assigned" (p. 74). ede and lunsford (1984) apply the concept of reader roles to composition theory and acknowledge that it is applicable to such nonfictional forms of writing as academic journal articles, business letters, and student academic writing.  although the concept of reader roles has been applied to several kinds of writing, the concept's relevance to computer documentation is largely unexplored. if computer documentation does invoke reader roles, then the notion of roles needs to be considered by writers as they plan and write documentation. writers would have to be certain that their documents invoke a role consistent with their intended uses. to explore this issue, i decided to re-examine the results of user protocols made during a test of the microsoft works v2.0 documentation at the microsoft corporation. microsoft works is an integrated pc applications program that contains a word processor, spreadsheet, database, and communications program.  a major goal of the original documentation test was to determine how well users could navigate in and use the works v2.0 alphabetic reference.1 the reference combined the features of a typical reference---for example, an alphabetic arrangement of key topics and commands---with features of user's guide, such as conceptual explanations of topics as well as step-by-step guides to commands and tasks. my re-examination of the data from the works test was prompted by two questions:  what kinds of roles might computer documentation invoke, and what cues might invoke them?  when users read computer documentation containing role cues, how do users respond to them?  in this paper i will answer these questions and explain how the answers can affect the writing of computer documentation.  m. simpson