Cover Moonrise over San Diego (Michael Burke/BlackBook)

In just a few decades, San Diego has changed from a sleepy military town, known mainly for its great surfing beaches, into one of the fastest-growing high-tech centres in the world. Following hot on the heels of the more mature San Francisco Bay Area and Boston regions in the United States, and giving sites in Canada, Europe and Asia a run for their money, San Diego provides an interesting lesson in how a high-tech hub takes root and expands.

In this Nature Outlook, we explore the factors that have shaped its success. The most important, and yet perhaps the most difficult for other regions to emulate, is San Diego's legendary 'brain trust'. The tradition of excellence at academic centres such as the University of California, San Diego, the Salk Institute for Biological Sciences and the Scripps Research Institute has provided a solid foundation for the start-up companies that have put San Diego on the map. For instance, information about cellular signalling pathways, painstakingly deduced by graduate students, postdocs and faculty members, has been used to develop drug targets. Fresh approaches suggested by physicists for beaming data through the air have led to new forms of wireless communication and enhanced the region's already strong reputation for telecommunications.

Once the seed of a new technology has been given life in the laboratory, San Diego-based venture capitalists and entrepreneurs are extremely active in aiding the next key step. They provide the financial backing necessary to see if the technology will yield a marketable application and they help new companies to commercialize promising technologies.

Although discovery and commercialization occur across the globe, most of the world's newest companies and products can trace their roots to just a few high-tech hubs. San Diego belongs to this group, and its famous networking environment has helped to build up a high level of investment in its own companies. The next challenge will be to ensure a steady stream of investment from around the world, to increase the diversity of revenue, and to keep the high-tech sector strong in this lean financial climate.

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