If it is a name brand lock, kits are available to re-pin the cylinder. For the fuss the few times I did it (not difficult, I just have other things to do ;-), I now just look for an outfit that will give free keys with a re-key or some other incentive and let them do it. The online locksmith dispatch service we tried once was a terrible experience. Apparently the site is subscribed to by locksmith wanna-bees. The guy we got mutilated the front door set. After a lot of pain we got the functional parts replaced but, never did get them to pay for the trim plate he destroyed.