By now, most investors and businesses know about the tremendous potential of Africa—the world’s second-fastest-growing region, topped only by emerging Asia. But it may come as a surprise that Africa’s growth is fueled not by resources but rather by a rising consumer market.

The continent’s consumer-facing industries are expected to grow by $400 billion, representing its single-largest business opportunity, by 2020. But many companies don’t know how to translate this potential into action, because of a dearth of market research. That, however, is changing. In one of the first studies of its kind, McKinsey’s Africa Consumer Insights Center surveyed 13,000 consumers in ten African countries, with a focus on the largest cities. Five categories of consumption were covered: apparel, financial services, groceries, the Internet, and telecommunications.