A difficulty in understanding Smith’s four stages of progress is that he more or less assumes progress but does not offer any clear theory of how it might take place. Smith almost seems to attribute progress to random events or serendipity, but using contemporary references, we should be able to develop a better understanding of his theory. We know Smith understood that self-interest was related to the natural desire to truck, barter, and exchange, and that he believed in the market as an important vehicle for coordinating cooperation and trade among people. In this regard, he understood that robust markets were decentralized with many producers and consumers. Moreover, Smith believed that progress was linked to the process of extending and diversifying the market. This was because extending and diversifying the market enhanced the opportunity for the further division of labor, and this increased the value of trading networks, which in turn further promoted wealth and asset accumulation. With this in mind, we undertake a closer look at Smith’s theory of progress and put it into a contemporary context by comparing it to market process theory.