We were having a discussion in the office today about how hard it is for men to find decent underwear that their wives and girlfriends will actually want to wear; a topic that becomes especially pressing at this time of year. Of course, if you're an eco-concsious sort of couple, you'll be sorted because pretty much every example I've seen of sustainable lingerie is both tasteful and well made. Take Enamore's collection, for example. It isn't cheap, but that only reflects the work that went into it (and the sweatshop labour that didn't). And your green goddess will love you forever for that.
But another way to buy undies-with-a-conscience is to go down the charity route. Pants to Poverty have been doing this for years, but if you want something a bit sexier than boy-shorts, you might want to check out Lost star Evangeline Lilly's lingerie auction. I don't think any of it's actually been on Lilly, but it's all good, gift friendly stuff and proceeds go to Task Brazil, the Brazilian street kids' trust.