In this article, 56K modems were introduced under two competing incompatible standards. The article shows the importance of competition between Internet service providers (ISP) in the adoption process. It shows that ISPs were less likely to adopt the technology that more competitors adopted. This result is particularly striking given that industry participants expected coordination on one standard or the other. It speculates about the role of ISP differentiation in preventing the market from achieving standardization until a standard setting organization intervened.