Insist that your top leaders get actively involved in developing middle managers—and not just delegate the job to others. At Kemp Technologies, a Manhattan-based firm with $30 million in revenue in 2014, each of the six members of the executive team mentors a few up-and-coming managers for one hour a month. Cultivating this talent pipeline keeps Kemp attractive to potential acquirers. “What they tend to look at is the second layer of leadership,” says CEO Ray Downes.

Cross-Train

Hold your intermediate executives accountable for resolving all complaints from customers and addressing comments in the employee suggestion box. Ask them to untangle the problems on their own and come to you only if they are stuck. Not only is
this an effective way to get them working cross-functionally, but it will also relieve pressure on the senior team. You will be shocked by how many teachable moments
the process creates.

Increase Flexibility

The most important role for midlevel execs is coaching their groups. To excel at that, they need to learn to vary their style depending on the person or team—and the opportunity or challenge they face. Use Ken Blanchard and Paul Hersey’s situational-leadership theory to teach them the ropes.
Only when they know when to teach or lead—or do neither—will they get peak performance from frontline employees
and be ready to move up.

Keep Them in the Ring

To climb the ranks, middle managers need to learn how to discuss difficult issues productively with their colleagues instead of relying on their bosses to referee. Datacolor, a provider of software, instruments, and services to ensure accurate colors in materials, products, and images, encourages this through its written “rules of engagement.” It asks employees to talk things out in person or by phone—not email—and to assume that their colleagues harbor no ill will. “Ninety percent of issues raised to me in the past no longer come to me,” says Albert Busch, CEO.

Invest Early

Cultivate up-and-coming employees using all these techniques long before you need them as leaders so that you’ll
be ready to pounce on new opportunities. At Kemp, executives have identified about 20 high-potential employees on their 175-person staff. Kemp gives them special assignments that will help them grow. It also invests $500,000 annually in education and training. With the company in a high-growth phase, “it’s key for us to be able to focus on that deeper bench of leadership,” says Downes.

This story is from the April 1, 2015 issue of Fortune.

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