Sorghum and pearl millet are primarily grown as subsistence food crops in Africa. Less than 5% of annual production is commercially processed by industry. This paper reviews the main constraints to the commercialization of these crops. These include a) low levels of productivity relative to commercial grain substitutes, b) high grain assembly and marketing costs, c) high processing costs, and d) the lack of familiarity of commercial food and feed processors with these crops. Efforts to promote the commercialization of sorghum and pearl millet face an essential conundrum. Farmers are reluctant to invest in the crop management necessary to improve the levels and consistency of production without reliable markets. But grain processors face little incentive to invest in market development as long as alternative grains are more consistently available at competitive prices. Suggestions are offered for resolving this challenge. These highlight findings drawn from recent market development efforts in southern Africa.