In addition to imbuing students with traditional field based knowledge, faculty in colleges of business administration have increasingly been asked to instill a sense of professionalism in students. Faculty members are, at the least, expected to bring a sense of professionalism to the classroom, and it is understood that this starts with professional dress on the part of faculty. A concomitant assumption with the expectation of professional behavior and dress on the part of faculty, is the belief that faculty dress has a positive impact on the classroom environment--thus on learning. The original purpose of this paper was to test whether or not professional attire made a significant difference in learning outcomes. Based on the time series analysis of measured outcomes, simply put, there is not a significant difference in performance at any reasonable level of significance. Actually, there is faint support for the contention that casual attire may be preferable. Anecdotal evidence seems consistent with the notion that students are more comfortable (that is they relate more easily to the instructor--better instructor immediacy) to the instructor used in this test when he was attired casually. Admittedly, there are certain advantages for professional attire. However, the suggestion that it makes a difference in student learning outcomes was not supported by this research. (Contains 2 charts, 18 footnotes, and 2 tables.)