The 75 million men and women born in a wave after World War II are now cresting onto the shores of retirement. One-quarter of the U.S. population is about to shut its collective briefcase, slip into sandals and take off for the Sun Belt.

That will leave a big hole in your information-technology department.

Railroad operator CSX Corp. has installed software to computerize the train-scheduling expertise of veteran dispatchers ("Track Changes," April, p. 61). Dow Chemical's chief information officer, Dave Kepler, who turns 53 this year and has 30 years at Dow, is tutoring six technology managers to spread his institutional wisdom.

What are you doing?

Novices may know new technologies. But they lack tacit knowledge of how your company actually operates—or the informal connections needed to get things done that don't appear on any org chart. That's OK when new hires come in ones and twos. But try getting things accomplished if you have to replace 25% of your employees in the next five years.

As its first baby boomers turn 60 next year, FirstEnergy Corp., a $12.5 billion utility in Akron, Ohio, will transfer the insight and knowledge of its long-timers to younger recruits.

The company plans to hire up to 75 new technology workers over three years. The gray-hairs will mentor incoming technologists for stints of a few months to two years.

The transfer of brainpower comes as FirstEnergy brings on 3,000 new employees companywide. They will ultimately replace the 23% of its workforce that is expected to retire by the end of 2007.

"We can't afford not to do this," says chief information officer Brad Tobin.

"Deep mentoring" and rotations through different departments are Tobin's two main tacks. Newbies will work alongside experts in programming, system maintenance, database management and the like for eight to 10 hours per week, absorbing the same information, attending the same meetings, performing the same tasks. Also, there will be classes led by internal managers, even drilling into informal knowledge such as who are the key players at FirstEnergy.

Then, rotations into customer service, finance and other basic functions will broaden the new hires' knowledge of the business and the technology that supports it. Java developers could learn to maintain the mainframe customer database for three months, then elect a three-month field gig to see how to extract natural gas from the ground. Network administrators could learn project management for a year, then explore how the sales group operates for a few billing cycles.

Giving employees the chance to learn things that pique their interest will keep them around, Tobin hopes. Retention is paramount.

He now retains more than 90% of his 675-member technology staff every year. But he doesn't expect that will continue unless he counters the baby boom exodus. Utilities generally don't draw a lot of new talent because they tend to use proven, stable technologies—nothing cutting-edge.

As Tobin points out: "I'd like to be able to look back 20 years from now and see an I.T. leadership team in place that was in this program."

You can check his success in 2025. Or you can do something today.

Inventory the technical and management skills of your tech staff. Predict what would happen if each person left.

Discuss with human resources and retirees how to get the skills out of retirees' heads before they go. List the specific tasks each person performs and technologies in use. Enumerate less concrete things as well, such as which person manages a specific meeting and the mental steps involved in solving a particular problem.

Orchestrating a mind-meld of this scale requires methodical mentoring, and stamina. "It won't be easy," Tobin says, "but it needs to be done."

Now.