ABSTRACT We synthesize the growing literature on asymmetric cost behavior—a new way of thinking about costs and, by extension, earnings. While the traditional cost behavior model describes a mechanistic relation between activity and costs, this alternative view recognizes the primitives of cost behavior—resource adjustment costs and managerial decisions. These primitives give rise to “sticky” and “anti-sticky” costs, along with traditional “fixed” and “variable” costs as extreme cases. We formulate an integrated framework of asymmetric cost behavior and review the empirical evidence in support of this framework and its implications for both cost and financial accounting research. We clarify empirical issues and show that recent contrary claims about the validity of findings in the literature are unwarranted because of econometric errors. We present new comprehensive evidence from Global Compustat, which demonstrates that asymmetric cost behavior is a pervasive global phenomenon. We also discuss research opportunities.