I'm taking a girlfriend of mine to get measured. I've been told she tries her bras on over a tshirt.

SEVERE body issues.

Your band size is actually the measurement under your breasts, plus 3, or 4 or 2-- depending. Until you get over 40", and then it should be the straight size. You can somehow confirm it by measureing above your breasts as well. I actually find it pretty confusing, since I measure 38", but if I add 4", the bra is WAAAY to big in the band. Even the 40" is a little big, although the Lane Bryant 38"'s are a little snug.

Also, I feel I have relatively small boobs for my size, and I wear a 38DDD and the underwire still doesn't lie flat on my chest-- but really, how could they be any bigger unless everyone else is like a J or H cup! However, all soft cup bras I can wear a much small size, becasue they just mush y breasts in.

Your band size is actually the measurement under your breasts, plus 3, or 4 or 2-- depending. Until you get over 40", and then it should be the straight size. You can somehow confirm it by measureing above your breasts as well. I actually find it pretty confusing, since I measure 38", but if I add 4", the bra is WAAAY to big in the band.

My size is so off of the "way you are supposed to measure" that I have no confidence in that system at all.

However, until I madeover my wardrobe, I definitely fell into the wearing the same (wrong) size I always wore. When I paid attention, and bought things because they fit, it made a huge difference. The big thing I learned was that every brand is totally different. I have like 3 different sizes, depending on the brand. Sadly, this is not true of all-in-one-bodys, which seem to be made to fit only short-waisted women.

Okay the bra fitting sizing is way more complicated then I thought!

and I wear a 38DDD and the underwire still doesn't lie flat on my chest

Then aren't you probably wearing the wrong size?

man, it's so confusing!!! But would be hilarious if men had these sorts of issues finding underwear that fit.

I have some of the Lane Bryant bras and they generally fit me well. The straps don't always stay where I've adjusted them to, which can be a PITA.

I think that's supposed to be a sign that too much weight is being carried by the straps.

I've heard enough reports of "I went in for a fitting and they gave me a XYZ even though I've always worn a ABC and it's so much more comfortable!" to believe that most women are wearing the wrong size bra. I mean, you're in the store asking for a fitting, obviously you need a new bra. What do the sales staff have to gain by giving you a different size if it doesn't fit better?

I figure my boobs are not big enough to need fancy bras to keep them in any particular place or anything...though is there a solution for "the straps are always too long until I put them on the shortest possible adjustment"? Though I'm not sure what the answer could be--a smaller bandsize wouldn't fit, and they dont' make a smaller cup. (And a bigger one is clearly too big). Hrm.

I mean, you're in the store asking for a fitting, obviously you need a new bra.

Well there's the selection bias-- you're going in to get fitted because your bras don't fit. That's not random. I find it dubious that an additional 70 to 85 percent are just waiting to be told that they need to be fitted. (FWIW I did get fitted and, surprise surprise, it was the same size as the bras I wear. Which fit.)

I can buy that 80% of women who get fittings are wearing the wrong size. And even maybe half of everyone else.