S&W Shield .45 in an IWB. Spare mag in back pocket. In colder weather, I will rotate back to my S&W 60 .357 with a backup speedloader in a jacket pocket. Defensive ammo at all times (other than the range). I know that a 9 mm seems to be a preferred choice of many here and that's fine. But if I ever have to use my weapon, I want the bad guy to know he's been shot.