Collaboration and social networking are driving the fortunes of a pair of up-and-coming open source platforms. In content management for the Web, Drupal is conquering new territory as companies look to build Web sites designed from the ground up to support social interaction. On the enterprise content management front, Alfresco has made collaboration and interoperability the keystones of its platform.

It shouldn't come as a surprise that collaboration is in the DNA of these software packages. After all, the open source model only works if communities of users and developers can work together to create and maintain products. Without that, they don't stand a chance against the deep pockets of commercial software companies.

As the economy tanks, open source proponents reflexively point to the low capital costs of acquiring open source software. But big customers want more than a bargain. They also want better. Thus, collaboration is more than just staying true to the open source credo of community and cooperation. It's also a smart business move. Drupal and Alfresco show us why.

Drupal was built from the beginning to let site builders include social software components, such as profiles, single and multiuser blogging, and social networks. And Drupal is winning converts. Sony BMG and Warner Bros. use Drupal to create sites for artists on their labels. The Onion, a satirical news site, also runs on Drupal. The New York City School system is using Drupal as part of a massive data-mining effort, letting 80,000 teachers and administrators share ideas on how to use testing and other data to spot lagging student performance and improve teaching.

Drupal draws on a strength that's common to other successful open source efforts: a vibrant community that drives innovation and lets companies tap the development efforts of thousands of people experimenting with the system.

That's one reason WorkHabit chose Drupal. The company builds large-scale social sites for media companies and other enterprises. "Some new Web 2.0 service comes out tomorrow, and by the day after, there's a connector," says Troy Angrignon, president and VP of sales and marketing at WorkHabit. "We get the advantage of that innovation."

Of course, community-based development has its downsides. Each time the Drupal core gets upgraded, companies that depend on particular modules must wait for the modules' creators to provide new code or write it themselves. And with thousands of available modules, it can be difficult for a company to know which are the most useful and well-supported. Unless a company can do its own development, its Web content management implementation may be at the mercy of people tweaking code in their spare time. Modules also need careful vetting. One developer says he does more extensive testing of Drupal modules than commercial software because he can't bank on the open source software's quality.

Those are some reasons WorkHabit isn't exclusively a Drupal shop. The company also builds sites for customers using Jive Software. "In some cases, it makes sense to go with a proprietary, closed source system," Angrignon says.