According to the ambivalence theory of fashion change, the increase of cultural ambivalence within a society is reflected by an increase in the heterogeneity of appearance-modifying commodities in the marketplace (Kaiser, Nagasawa, & Hutton, 1995).* The purpose of the present study was to see if evidence to support this theory could be found in a historical context where ambivalence about a cultural category occurred. Specifically, white, middle- to upper middle-class American women's daytime fashion of the late 19th and early 20th centuries was studied for evidence of increasing diversity as women's social roles changed and became increasingly ambiguous;A sample of 252 illustrations of women's daytime fashions was systematically selected from every third year of the March, June, and October issues of Harper's Bazaar and the Delineator. A visual analysis instrument composed of various levels of measurement was designed to obtain a detailed description of each illustrated costume;The sample was coded by multiple individuals to establish interrater reliability of the instrument. Spearman rank correlation coefficient was used to test for trends in diversity in the time series data. Limited evidence was found to support the amivalence theory of fashion change. Findings underscored the need to consider a variety of factors which may shape and drive fashion change at any given place and time. ftn*Kaiser, S., Nagasawa, R., & Hutton, S. (1995). Construction of an SI theory of fashion: Part I. Ambivalence and change. Clothing and Textiles Research Journal, 13(3), 172-183.