About 400,000 people work at IBM, scattered in offices all over the world. To help them work together, the company has been conducting large-scale internal experiments with social software. What started as ad hoc experimentation has become a focused effort driven by the company’s senior management, reaching almost all the company’s employees.

As far back as 1997, IBM built an Intranet directory in an effort to help employees find others with the skills and experience they were looking for. For several years after that, employees informally built applications on top of that infrastructure. While many of those tools were helpful, they often didn’t have the technical support they needed to really improve work at the company, says John Rooney, who heads the Technology Innovation Team in IBM’s office of the CIO. “Projects might be running on a server under someone’s desk,” he says.

Five years ago, IBM started the Technology Adoption Program (TAP) to facilitate employees’ software experiments. The company created a website with a catalogue, where employees could find projects to try out, and supplemented it with infrastructure to host and develop the projects.

TAP hosts a variety of projects, from early tests of planned commercial products to tools and plug-ins designed by employees in their spare time. “Many things enter TAP without a specific agenda,” Rooney says. IBM then looks at how people embrace and adopt the projects, seeing them through a life cycle that can lead to broader deployment if early indicators suggest value.

For example, Rooney says, many companies struggle with finding an efficient way for employees to share files. When people use e-mail for this purpose, it’s often hard to tell which version of a file is the most recent, and duplicate files are stored all over the place. For years, IBM’s IT office had a file-sharing service in place, but hardly anyone used it. An employee reconceived the service, adding better social features. The new version caught on throughout the company and eventually led to a product that IBM offers to its customers.

Measuring the success of social tools can be tricky, since many of these technologies serve intangible goals such as making a geographically separated team feel more cohesive. However, TAP tracks ratings and adoption levels for its technologies. Employees of IBM’s research arm also conduct studies on tools shared through TAP to quantify their effect. The company says that Lotus Connections, which includes many features that originated in TAP, is the fastest-growing product in IBM’s history.

In its social experiments, IBM has “sucked in virtually all of the concepts from the Web and Enterprise 2.0 worlds,” says Michael Coté, an industry analyst with RedMonk. “I like to think of what they have as your own version of the Web, for behind the firewall.”

At IBM, employees are participating in what Rooney calls “a truly social community.” About 358,000 employees are registered for IBM’s internal version of Connections—effectively 90 percent of the work force. More than 124,000 employees are registered to be early adopters through TAP and have committed to making a bigger investment in developing new internal social technologies.

He adds that the company further supports social experiments by using the tools for companywide events known as “jams,” which are conversations between senior management and employees. By having senior management initiate conversation through social technology, Rooney says, “we send a really important signal that we value a certain type of interaction.”