Knowledge has become the new premium fuel for economic growth in the 21st century. Knowledge fuels new ideas and innovations to boost productivity – and to create new products, new firms, new jobs, and new wealth. Some analysts estimate that knowledge-based activity accounts for half of the gross domestic product in Western industrialized countries. In the United States, knowledge-based industries paced gross domestic product growth from 1991 to 2001, and their importance has accelerated since 1995. ; In rural America, as elsewhere, a variety of factors make knowledge-based growth possible: high-skilled labor, colleges and universities, vibrant business networks, and infrastructure. Some rural communities are already leveraging these assets to transform their economy. Many other rural places, however, have yet to tap this rich economic potential. ; Henderson and Abraham use empirical evidence to identify the factors that are essential to rural knowledge-based activity. They then describe how some rural communities are leveraging these factors to build their own knowledge economy.