Only bike I had stolen was in college, a beater of sorts that I left on my girl friend's doorstep while visiting. Not smart by me. The only time I leave my bike unattended is at a convenience store when I go into to get a snack, or if it's on my car. I have a cable lock for when it's on the car but I rarely use it, plus it's on the roof of a small SUV and hard to reach without a step stool. If I'm going to be inside for awhile, like at a restaraunt, I'll park where I can see the bike and car, but I have never had any trouble. I also don't usually go to heavily populated areas with my bike, so I think that cuts down on the odds of some pro bike theives being around.