ll companies, from major multinationals to start-ups, face a common challenge: how to grow their businesses so they can boost earnings and enhance the value of their shares. Far too often, however, firms find it difficult to sustain growth because they become risk averse and, as a result, opt for incremental product and service improvements instead of major initiatives, according to a study by a Wharton marketing professor.

George S. Day, who also serves as co-director of Wharton’s Mack Center for Technological Innovation, says companies can avoid lackluster growth by better understanding the risks inherent in different levels of innovation and achieving a balance between — using two terms he has coined — BIG I innovation and small i innovation. In his study, Day discusses how executives can properly assess risks and then seek creative ways to reduce risk exposure.

Day, a consultant to many Fortune 500 companies, says his research is the outgrowth of years of thinking about the problems that companies face in trying to set and achieve growth targets. Growth — particularly “organic” growth that comes from improving a company’s performance from within rather than relying on acquisitions — is so important that it is at the top of the agendas of some 80% of U.S. chief executive officers, according to Day.

“These executives know that the expectation of superior organic growth is the most important driver of enterprise value in capital markets,” Day writes in the paper, titled “Closing the Growth Gap: Balancing BIG I and small iInnovation.” It is also a less expensive way to grow because a firm typically pays a premium to acquire another business. Yet studies have shown that only 29% of managers of major corporations are highly confident they can reach their organic growth targets.

A combination of factors can make organic growth hard to sustain. For one thing,