Research by Darkenwald and by James and Day supports the contention that instructor behavior is a critical factor in shaping the kind of classroom environment desired by adult learners. Darkenwald developed the Actual and Ideal Adult Classroom Environmental Scale (ACES), which measures seven dimensions: involvement, affiliation, teacher support, task orientation, personal goal attainment, organization and clarity, and student influence. Discrepancies between instructor and student responses for the Actual ACES suggest that teachers are unaware of the social environment students actually experience. Research conducted by James and Day identified six categories of instructor behavior that contribute to making an adult learning environment less than optimal: attitude, attitude/behavior, behavior, behavior/task, environment, and task. They used McClusky's theory that margin is the relationship between the demands made upon an individual and resources used to cope with demands. Instructors can create optimal conditions for learning in the adult classroom by being aware of their role in creating the climate, changing their behavior or attitude, understanding learner concerns beyond the classroom, and involving adult students in establishing the climate. (NLA)