Sol Price and Sam Walton changed retail in the twentieth century. Price changed retail by combining knowledge he assembled from real estate law and from the firms he observed to find creative ways to innovate in discount retail. Walton too combined and redeployed knowledge—in some cases, knowledge he obtained by observing Price. Walton also used knowledge acquired from studying retail logistics to develop a supply chain that dramatically lowered costs and passed those savings onto consumers. Both succeeded by developing organizations that effectively deployed entrepreneurial judgment. Their careers provide informative examples of the judgment-based approach to entrepreneurship.