Grayson, who is also director for the school's Doughty Centre for Corporate Responsibility, told HR magazine organisations are more likely to face pressures from their workforce than their customers around being responsible corporate citizens.
"If you don't act in a responsible way it's true that consumers will be harder to engage," he said. "But talent will be the big driver. People already want to work for employers they identify with.
"The pressure on employers to account for their impact on their surroundings will only increase."
The Doughty Centre was involved in research with the Financial Times' FT Remark and Coca-Cola Enterprises (CCE) ahead of the CCE Future of Sustainability Summit.
The poll of 50 CEOs and 150 recent business school graduates (called 'future leaders') suggests 88% of CEOs believe businesses already have a clear social purpose. However, only 19% of future leaders agree.
Grayson believes leaders in the future will need "clear and defined strategies" to ensure social purpose is embedded in their companies.
"Aligning reward and incentive, recruitment strategies and senior people leading by example will be key," he said. "In the future social purpose will just be part of business. The next generation of leaders will need to spend a lot of time defining the purpose of the company."