This guest post was written by San Francisco Mayor Gavin Newsom, who was elected to the position in 2003 and reelected in 2007. In this guest post, Mayor Newsom announces a new open source software policy for San Francisco and discusses the benefits of choosing open source technology.

One of the greatest technology changes of our times is the rise of open source software. It represents a different way of developing software, one that is public by its very nature. The underlying source code is not copyrighted and therefore available free of charge to read, modify, and build upon. Update: Based on feedback, we plan on using the open source definition from the Open Source Initiative. Thanks to all that pointed this out. This new definition will be reflected in our policy.

Open source software is created by the people for the people and as such is ideal for government. To that goal, I am extremely proud to announce today the nation’s first open source software policy for city government. San Francisco's new policy requires city departments to consider open source software equally with commercial products when purchasing new software. The opportunities with open source are tremendous: lower costs, greater agility, better reliability, improved security, and increased innovation.

Under the leadership of our City CIO, Chris Vein, and the Department of Technology, we have witnessed the benefits of open source with shorter implementation times and lower costs. We have seen this with my web site, DataSF.org, RecoverySF.org and our 311 integration with Twitter.

Open Government is Already Paying Dividends

Moving forward, there is an opportunity to save millions of dollars in software costs by using open source software. We are only scratching the surface. We can and must do more in the face of historic budget deficits. Our new open source policy requires the City to choose new technology wisely.

This is just the beginning of the Open Gov movement in San Francisco, but our early efforts are paying off.

Since the launch of DataSF last summer, the City’s clearinghouse of government datasets, we have seen our tech community create new services and products never dreamed of within the walls of government. And now we are giving people access to technology systems like our 311 call center through open source, so they can decide how and when they interact with government.

We face many challenges today, none more urgent than the economic crisis, but with it comes an opportunity to seek new ways of governing. In San Francisco, like other cities, we are using this opportunity to engage our greatest resource, the public, to build a government that works better for all of us.

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Image courtesy of iStockphoto, SamValtenbergs