And even if you're only planning to use the software internally, it's important to ensure that the legal department understands the numerous types of licenses available, Driver says. "Restrictions vary, sometimes dramatically," he says. "You don't want to get a letter from your lawyer with an injunction because your open-source solution violated someone else's intellectual property."
Fitting open-source technology into your current infrastructure is another thorny issue. Three years ago, Roy Mentkow, director of technology for the city of Roanoke, Va., decided to transition from Microsoft Office to OpenOffice. However, for some users, desktop applications were heavily integrated with Lotus Notes workflows. "We had to ensure OpenOffice worked well with Notes on an application-by-application basis," Mentkow says. "That was something that snuck up on us."
In the end, the city migrated about half of its 900 users, resulting in $140,000 in savings. Still, Mentkow says, the savings won't come all at once but rather when those desktops would have been upgraded to a new version of Microsoft Office.
It's also important to look beyond another widely touted benefit of open-source software: the ready pool of developers who are familiar with the technology and see the prospect of using it as a retention or hiring plus. While it's true that developers are plentiful and eager to work with open source, that expertise can come at a price.
"If you asked a developer if they'd like to work with open-source or commercial software, eight times out of 10 they'll say open source," Lyman contends. And some developers may charge less than developers who work with commercial products.
Hamadeh says that with SugarCRM, it's even possible to "have a local student come in and program something in a couple of hours," Hamadeh says, or a tech-savvy business person can create custom modules. But, he cautions, while there are some SugarCRM consultants who will do a great job, they can be expensive, so having internal IT talent can help you avoid added costs.
Brisbin points out that the success of open source at NPC is due largely to the fact that its developers have a breadth of knowledge and are willing to work outside of narrowly defined silos.
"We have small development teams, and we cross areas of responsibility," he says, noting that he routinely moves among RPG, Java, Web front-end development, PostgreSQL and the underlying application system. "There is a critical mass of information you need to have as a developer to do open source effectively," Brisbin adds.
And then there's one of the more hard-to-quantify costs: cultural change. Mentkow says Roanoke's move to OpenOffice involved changing the culture as much as it did changing the desktops. "Cultural change does not happen in moments," he says. "As we move to different platforms and different standards, what we have to see is an acceptance of those changes."
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