About a year ago, computer maker Dell Inc. needed a sales executive in China. Managers looked in an internal database that tracks employees' skills and experiences, where they found a sales leader who was finishing an assignment in Australia. The Chinese post required someone gifted at setting business goals and leading others; this man not only had experience in the Asian-Pacific region but also notched high marks on those skills. The employee got the job.

That is the promise of a "skills database," an increasingly popular tool that companies use to track employee talents. Executives hope to tap the databases to help fill specific needs, as Dell did; to anticipate, and head off, looming talent shortages; and to aid career-development paths. The tasks take on additional urgency as baby boomers begin to retire.

The concept is disarmingly simple. Employers create a database with the skills and credentials of each employee, such as prior jobs, technical expertise, training, certifications, coaching aptitude, geographical experience, languages spoken and career aspirations. Human-resources staffers and operating executives can then analyze the data to identify strengths and weaknesses of the work force.

But simple ideas often prove difficult in practice. Employees can misstate or deliberately overstate their qualifications. And some managers may withhold information, fearing that their most skilled employees will be poached by others.

"It's a great concept, but it's a hard thing to operationalize," says Ed Jensen, a partner in the human-performance practice of consulting firm Accenture Ltd.

Mr. Jensen recalls a transportation company that set up a skills database a few years ago for its information-technology staffers. Employees were supposed to enter their skills and proficiency levels, and managers were to review the reports. But overworked supervisors mostly rubber-stamped employees' accounts. "People were way overstating the amount of skills they had," Mr. Jensen says. As a result, the company didn't recruit aggressively enough, ran short of key skills and had to hire consultants to complete important projects.

At a financial-services firm in the Northeast, Mr. Jensen says, executives tried to track employees' proficiency at a handful of "core" skills such as project management, communications and leadership. But the executives didn't sufficiently define the skills or levels. Employees used their own judgment, and the company ended up with inconsistent, mostly meaningless data. The company created more specific definitions but ultimately decided it wasn't worth the effort and abandoned the project.

Other employers have overcome these sorts of problems and say skills tracking is worth the effort. Consulting and staffing firms are among the most advanced because their businesses depend on how they deploy staffers for various projects. Most other big employers have at least a basic "talent profile" database listing easy-to-glean information such as what jobs employees have held and what languages they speak, says Kirk Rogg, a senior vice president at Aon Consulting in Chicago. But he estimates that fewer than one-fourth of employers have the detailed information needed to accurately forecast potential skills shortages.

Some companies rely on managers to enter and update employees' skills. Others ask employees to enter their own information but require managers to approve the submissions. Some more sophisticated systems automatically enter information from performance reviews into the database.

At Dell, employees complete a 15- to 20-minute self-assessment listing prior experience and skills and career preferences, such as willingness to work overseas. They can update it any time. About twice a year, supervisors review and discuss the information. To make sure that managers do the reviews, Dell includes completion of these discussions in supervisors' performance reviews. By now, "it's institutionalized," says Michael Summers, vice president of global learning and development at Dell.

Mr. Summers says the system has helped the company staff its Asia-Pacific operations, a big growth market, including the sales job in China. More generally, the system helps the company gauge its bench strength. "You can pretty quickly see where it looks like you have a pipeline and where you don't," Mr. Summers says.

Geisinger Health System of Danville, Pa., is starting to build a skills database, says Jack Latshaw, assistant director for technology education services. Geisinger, which operates hospitals, doctors' offices and a health-maintenance organization, has long tracked what training courses employees have completed. Now, the company wants a more sophisticated forecast of potential skills gaps as the baby-boom generation retires, Mr. Latshaw says.

"In the younger work force, there's a lack of experience," he says. Mr. Latshaw says he hopes the system will identify skills, in particular leadership abilities, for which Geisinger may face a shortage in a few years. "That's your signal that you've got to get some kind of a program to step up to fill these gaps, like a training program or mentoring and coaching by the older employees," he says.

Mr. Latshaw concedes the system has limitations. The software may identify employees whose skills and credentials suggest they are ready for management roles. But it is harder for a program to gauge softer skills, such as whether an employee can manage other people. "Although they have all the skills and training, how do you figure in the gut-feeling factor?" Mr. Latshaw asks. "I don't know that you can do that with a skills-management system."