This article originally appeared on Forbes.com.

If anything characterizes a growing business, it’s energy. You need energy to operate at speed, to stay focused on customers and to do battle with larger incumbents. But beware: As you grow, your company may see the rise of the same creatures that infest your larger competitors, the energy vampires.

Energy vampires are the people who make you stop and think, Do I have the energy to take this call? when their names come up on your phone screen. They have demonstrated repeatedly that they will suck the life out of you in every interaction.

Other telling signs: They send out a lot of templates. They schedule lots of meetings. They exercise pocket vetoes on key decisions, and they stop action with their requests for one more round of analytics. They wait at the other end of emails, ready to fire off missives that force your people to stop serving customers and instead respond to yet another information request.

I recently conducted interviews with large-company CEOs about the nature of their work and found that preserving energy was critical. One CEO noted how difficult it was for him to do his job when he was tired. “For me, the job has become a battle for energy, so I’ve become a lot more selfish about preserving that energy,” he said.

What is true for these CEOs is equally true for CEOs of smaller firms. If your company has grown to the point where it is beginning to harbor energy vampires, root them out. It’s not acceptable for anyone to be a net drain on the energies of others. After all, that energy is the lifeblood of your company.

James Allen is co-leader of the global strategy practice at Bain & Company and co-author of the upcoming book “The Founder’s Mentality.”