Jeanne Shaheen, the U.S. Senator from New Hampshire, wrote in her recent Huffington Post article that women-owned businesses have become "the nation's job-creation machine” in the US. The good news is that between 1997 and 2014, according to an American Express study, the number of women-owned firms in that country grew at 1½ times the national average; and revenue and employment growth among women-owned firms tops that of all other firms except for the largest, publicly traded corporations. This progress in the US sends a positive message to the rest of the world, particularly here in Africa. The bad news is that the continuing glass ceiling for small business is not only holding back women entrepreneurs; it is also depriving Africa's economy of vast untapped human capital, creativity, and innovation. We need to level the playing field for women in small business on the continent as a whole, ensuring more equal access to credit, capital, counseling, and contracts. Warren Buffett famously said that one reason for his extraordinary success is that he was competing with only half of the world. It's time to fully unleash the other half.