An issue that is often discussed in ESG investing is whether a firm mired in a controversy is having a one-off event, or is it part of a trend pointing to underlying ESG issues? This question has important implications for the performance of its equity and debt securities. This is a meta-analysis piece based on published research papers.

There is unprecedented interest in ESG (Environment, Social, Governance) investing, also known as sustainable or responsible investing. However, the top concern among investors looking to integrate ESG into their investment process is the issue of multiple ESG rating providers, and the fact that the same corporate may get vastly different ESG ratings from different ESG raters. Why does that happen? What to do about it?