Chlordane, the long-standing favorite among termite killers, was very effective. But it was outlawed 5 years ago because of health and environmental risks associated with its use. The performance of new substitute materials is far less predictable. They are often confused with termites. Unlike termites they have pinched waists and elbowed antennae.
Termites have straight bodies and antennae.
As with termites, there is a winged version too. Carpenter ants can do significant structural damage, but are more a nuisance than a structural problem. When it comes to remediation, home owners make the best detectives and should attempt to eliminate carpenter ants themselves. If you see the winged form in any number indoors, you have a problem. If you see sawdust raining from your ceiling or from any indoor cracks, you have a problem.