Academic selectivity plays a dominant role in the public's understanding of what constitutes institutional excellence or quality in undergraduate education. In this study, we analyzed two independent data sets to estimate the net effect of three measures of college selectivity on dimensions of documented good practices in undergraduate education. With statistical controls in place for important confounding influences, an institution's median student SAT/ACT score, a nearly identical proxy for that score, and the Barron's Selectivity Score explained from less than 0.1% to 20% of the between-institution variance and from less than 0.1% to 2.7% of the total variance in good practices. The implications of these findings for what constitutes quality in undergraduate education, college choice decisions, and the validity of national college rankings are discussed. (Contains 5 tables and 1 endnote.)