"We're taking on larger projects now, but we've never wanted to become too dependent on a single project," says Ziegenfuss. "We don't want to take a 600-mile pipeline project, take on a bunch of employees, then not have anything that big coming behind it. We want to avoid having to ramp up and ramp back down."

Hulet and Ziegenfuss say the company's greatest strength has come from serving a number of repeat clients while actively marketing itself to new customers. The company, which began operation in 2002, started out with "a couple of clients," Ziegenfuss says, but now serves more than 100. "And we haven't lost one yet," he adds.

"Our work with [EN Engineering] has only increased over the years," says Doug Staebler, vice president of engineering and construction for D.C.-based utility Washington Gas. "They work on probably 70% of our jobs. In such a close-knit industry, if you do well, everyone else hears about it. And I think it's important to them that they've maintained their relationships even as they've gotten bigger."

"Our name recognition 10 years ago was nothing," says Hulet. "Now … the market has begun to seek us out."