We were at my ILs a few weeks ago and it was a GORGEOUS day with low humidity, a wonderful breeze and cooler temps after having a record breaking summer. It was time for us to go to dinner and my MIL said to my FIL "You close the windows in here, I'll get the den." Both my husband and I said "Leave them open!! Let the nice air in!" and they wouldn't do it. I said that I left my windows open at home so that the house could finally get aired out and they were shocked!! "You leave your windows open when you go out?? Even on the first floor??" Yep!! We do!! Sure, we lock the doors but the windows? Unless it's going to rain, we leave them open in good weather. Then I remembered that they even lock the house when they are out gardening because my MIL locked herself out of the house numerous times where we had to go over with the key to get her back in. Of course she wouldn't give a key to a neighbor for fear they might steal something!! Oh - she said "Well, you must live in a better neighborhood than we do." Yeah, they lived in one of the nicest neighborhoods around for years and just 3 years ago moved to a retirement community that is well watched by security. LOL So, do you lock up when you go out? I'm talking under regular circumstances and not going away on vacation. Going to school, going to work, going out for the day, etc. Thanks!!