Using 24 college and university teachers, this study investigated the effect of teaching styles on adult student learning and analyzed the results of a factor breakdown, interactions between teacher behavior and class and student characteristics, and profiles of teacher effectiveness. Gains in factual information were positively related to teacher clarity and expressiveness and to lecturing; gains on a comprehension test were associated with a moderate position on the permissiveness-control continuum and with energy, aggressiveness, and flamboyance. Students gave most favorable evaluations to teachers scoring high on warmth and clarity. Students with jobs did best with relatively aggressive teachers stressing factual participation; women did best under teachers scoring high on lecturing. Students below age 19 learned factual information best from teachers stressing student growth; those over 19, from teachers stressing factual participation. Students in large classes learned facts best from permissive, warm, flamboyant teachers stressing student growth; students in small classes did best with teachers who lectured, were relatively "dry," and emphasized factual learning participation. Implications and limitations of the study were also noted. (ly)