The diffusion of innovation is a multilayered process that involves five main steps: knowledge, persuasion, decision, implementation, and confirmation. Between 1951 and 1963 California State Librarian Carma Zimmerman Leigh utilized several methods to introduce and eventually develop public library cooperative systems statewide. But the process was not easy. A study conducted by Ed Wight provided the knowledge needed to persuade the state’s librarians to adopt (or decide on) a library master plan for California, which was finally implemented with the passage of the Public Library Development Act in 1963. Confirmation occurred shortly afterward with the successful creation of public library systems statewide.