A study explored the complexities of audience adaptation by examining the relationships between writer/audience proximity, register, and overall quality in essays written for assigned audiences. Subjects, 100 college freshmen, each wrote one essay in response to two audience-specified tasks in which subjects were to write persuasive letters to readers with whom they had been acquainted--one to a prospective employer, the other to the editor of a student newspaper. Findings showed that writers who responded to tasks specifying a singular audience constructed versions of that audience that varied according to their perceptions of psychological proximity. Results also indicated that audience adaption may not be as categorical as previous research on audience specification presumed. Instead of either adapting or not adapting to an audience, subjects seemed to adapt to the audiences in degrees. In addition, the degree of adaption appeared to be systematically affected by the social context suggested in and surrounding writing tasks and by the social knowledge that writers bring to tasks. Specifically, results of multiple regression analyses indicated (1) that students internalize different psychological versions of singular assigned audiences, (2) that registers vary consistently with the psychological proximity assumed by individual writers, and (3) that choice of register and proximity affects quality ratings. (Nine pages of references are included. The specified audience assignment involving a letter to a prospective employer is appended, as is an audience intimacy index for this task.) (JD)