What's the Difference Between IDPA and USPSA?

In the live chat for the last Triangle Tactical Q&A; show, Austin asked "What's the difference between IDPA and USPSA?" I didn't have time to get to it in the Live Q&A; show, so I thought I'd talk about it here on the main podcast.  Here's the rundown: Concealment: IDPA requires you to have your gun concealed. You'll generally see people using a vest to conceal their gun, but a vest is not required. USPSA does not require your gun to be concealed. Divisions: For the most part, the different divisions in each game are somewhat similar-ish.  In USPSA there are 7 divisions. This is really high level, but here's the breakdown: Production - This is the division I shoot. You'll want to shoot 9mm in Production. You're limited to 10rds in a magazine, and in this division you'll see a lot of Glocks, M&P;'s, CZ's and Tanfoglio pistols.  Carry Optics - This division is for pistols that have slide-ride optics. My advice here is to buy an optic with a GREAT warranty. I've seen a LOT of them break, and they're expensive. Pistol Caliber Carbine - Pretty self explanatory. You're generally going to see 9mm AR's, that sort of thing. Single Stack - This is a division for 1911 pattern pistols. Limited - You can basically do whatever you want to your pistol in Limited, except for have a compensator, optic, or weapon-light. You'll generally see .40S&W; 2011 pistols in this division. Open - This is the division you probably think of when you think of a race-gun. 2011 pattern pistol, red-dot optic, compensator, chambered in .38Super or 9mm major.  IDPA has a few less divisions: Stock Service Pistol - Pretty similar to USPSA's Production division. Guns like the Glock 34, Glock 17, M&P;, etc. will shoot in this division without many modifications.  Enhanced Service Pistol - ESP allows some more modifications than SSP, as well as single-action pistols. Custom Defensive Pistol - This is basically the 1911 division, but you can shoot other .45ACP pistols here too. Compact Carry Pistol - A division for the smaller guns that people actually carry concealed. It's basically for your S&W; Shield sized guns, up to about the Glock 19 sized guns.  Back-up Gun - This is or the teeny tiny guns like the Ruger LCP, etc.  Stages: USPSA stages can have up to 32 required rounds. This means you'll need to make sure you've got enough magazines to shoot all that.  IDPA stages are limited to 18 rounds per stage, which means you need a little less ammo, and other gear to get started.  In USPSA, you're basically presented with a problem, and it's up to you to come up with a stage plan, and solve the problem yourself.  In IDPA, you'll be told a bit more about how to shoot each stage. "Start here, shoot these targets from here, those targets from there, etc." USPSA Classifier Updates Also in the live chat for the last Triangle Tactical Q&A; show I had a few people asking me about my thoughts on the announced USPSA classifier updates. I read the entire thread over on Doodie Project, and honestly, I think the whole thing is a big nothing-burger. I think they should be updated frequently, and I don't really have an issue with how it's being done.  Plug of the Week: Jessica Nietzel wrote a FANTASTIC article over on the Shooters Mindset blog about subjectivity in RO calls in USPSA.  DQing new shooter SUCKS.  DQing you friends SUCKS.  But, sometimes it needs to be done. Go read it.