Despite 40 years of research on the relationship between corporate environmental performance (CEP) and corporate financial performance (CFP), there is no generally accepted theoretical framework that explains the contradictory results that have emerged. This unsatisfactory status may be attributed to the fact that linear models dominate the research. Based on an international sample of 2361 firm‐years from 2008 to 2012, we find empirical evidence of a non‐linear, specifically a U‐shaped, relationship between carbon performance and profitability as well as between waste intensity and profitability. The same result holds for the relationship between carbon performance and stock market performance, but solely for manufacturing industries. Our empirical findings provide evidence for the theoretical framework of a ‘too‐little‐of‐a‐good‐thing’ (TLGT) effect, which indicates that the type of relationship (positive, negative) depends on the level of CEP. More precisely, there is a negative CEP–CFP relationship for companies with low CEP and a positive association for high CEP. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment