Comment: 45 pages, 4 tables, 1 figureHow does an entrepreneur's social capital improve small informal business productivity? Although studies have investigated this relationship, we still know little about the underlying theoretical mechanisms driving these findings. Using a unique Zambian Business Survey of 1,971 entrepreneurs administered by the World Bank, we find an entrepreneur's social capital facilitates small business productivity through the mediating channels of firm financing and customer relationships. Our findings identify specific mechanisms that channel social capital toward an informal business' productivity, which prior studies have overlooked.