In 2014, Larry Fink started writing letters to the leaders of some of the largest publicly listed companies, urging them to consider the importance of environmental, social, and governance (ESG) issues.

Fink is the chairman and CEO of BlackRock, one of the largest asset management houses in the world. The firm’s success was rooted in its cost-effective, passive investment products that rely on tracking indices and funds. But Fink wanted his firm to engage with the companies in which they invest and hold them accountable for their social and environmental impacts.

What role should investors play in urging business leaders to take ESG issues more seriously and enforcing compliance? Harvard Business School professor George Serafeim discusses the merits of Fink’s approach, the importance of corporate investments in ESG themes, and how to lead a company driven by purpose and profit in his case, “BlackRock: Linking Purpose to Profit,” and his new book Purpose and Profit: How Business Can Lift Up The World.