The challenge of creating an effective and appropriate library collection has been further tested by the recent advent of what Clayton Christensen has termed “disruptive technology.” In his well-known study, The Innovator’s Dilemma, Christensen explores the impact of technological change on the business and other communities. For Christensen, technology can either be sustaining or disruptive. Sustaining technologies improve the performance of products and continue to make them valuable to the consumer. Disruptive technologies, on the other hand, initially underperform in the marketplace, but have a tendency to improve their quality at a rapid rate and eventually replace the established technology. The result, as Henry Lucas noted, was that the customer benefited greatly from “more choice, more flexibility, more options.” For libraries, the availability of electronic books (ebooks) that can be accessed outside of the traditional catalog via a patron-driven or demand-driven process (DDA) is indeed disruptive to the entire fabric of established collection development procedures.