Inspired tangentally by blackrabbit’s thread on keeping mementos of one’s exes…
In what context have you met the people you’ve become seriously (or not-so-seriously) involved with?
Shared interests.
In my experience the best way to meet people you will get along with is through hobbies or volunteer work.
If you have a passion for animals, volunteering in an animal shelter is a great way to meet people who also love animals. Or if you love hiking, joining the Sierra Club and going on group trips is a great way to meet others who love the great outdoors. Ditto for playing chess, building models of WWII aircraft, fishing, being in a book club, or acting in a local theater group.
It’s how I met my husband, my mother met her husband, and all 3 of my sisters met their husbands.
Option 2, "We meet through mutual friends and “click"without a platonic friendship first” vs “From my circle of friends” is a bit limiting, given there has often been a bit of platonic getting-to-know-you, friend of a friend out with my buddies thing, that doesn’t always turn into what I would deem friendship before the dating starts. This has been my experience a few times, anyway. I chose option 1 anyway because it’s less inaccurate than option 2.
I met my only girlfriend through work, though it was actually mutual friends/co-workers setting us up.
Of the other women I’ve been acquainted with, all were met online, between three different sites, only one of which was relationship oriented.
Other: I met a roughly equal portion of my dates/girlfriends at parties, in class (college), at work and through friends.
The last group were by far the most successful in the long term, including my fiancee.
A bar. Not a singles bar, just a regular old bar.
First husband, college and circle of friends.
Dates in between two husbands–personal ads (it was the 80s) and grad school.
Second husband–bar.
Since last divorce–bars, online dating, and work. Once a guy approached me at a grocery store to say that he couldn’t stop staring at me because I was so beautiful, and I really wish one of us had gone beyond introducing ourselves, because that’s all we did. He may have been a supermarket psycho, but I would have liked to have known.
I rarely meet men through friends, for some reason. Could be because most of my friends are single women and want to keep any single man for themselves, or at least to keep them as a possibility.
School.
First girl: junior high
Second girl: high school
Now-wife: high school
Usually a bar.
Current romantic interest and I met through mutual friends. I had gone visit them, passed by their lab, and he was there. No “friendship” part, straight to flirting/courting.
The one person I hooked-up who was “work-related” served me well to teach me not to do that again.
Gay bars.
Back in my single days, they were great places to meet friends, and make new ones.
Met my SO in such a bar just about 29 years ago, and we’re still together - so I guess it works for some people.
The first few were from high school or college.
My ex and I met due to shared interests-- we were playing a MMORPG and had named ourselves after characters from the same book series.
My current boyfriend is a co-worker.
I chose option 2 (met through mutual friends, no platonic friendship first), although it’d be more accurate to say ‘blind dates set up by friends/family.’ I come from a culture big on blind dates, although I did meet some guys on my own through the broader way described in option 2, like when he and I were invited to the same Sabbath meal, say.
I used to wonder if it said something about me that no guy who’d ever known me for more than 48 hours ever asked me out. I managed to get married anyway, but he was a blind date, so my record still holds 
I’ve met guys all different kinds of places. I chose more than one option in the poll. My first husband I met at a bar; the second, at the daycare; and my third at work. Other “significant others” I’ve met have been from those kind of encounters or through mutual friends.
I met my first boyfriend when I went white water rafting with some friends and he sat next to me on the bus! We were both in wet suits and I wasn’t exactly looking my best, but he nonetheless started talking to me. That was by far the most interesting way I’ve ever met a guy.
I voted “Working Together” and “other” because I’ve only ever met SOs at school or university in shared classes.
Work or school.
Nerdy places. Online games, SCA-type groups, RPG clubs, stuff like that.
I suppose I should answer, since my thread inspired this one.
I avoid dating women from work and my circle of close friends. My marriage was pretty isolated and lonely, and it ended badly. I don’t want to do anything to jeopardize the platonic relationships that I’ve since worked hard to rebuild, even though the chances that an intimate relationship could go as sour as my marriage are pretty slim.
Dates are easy to get. Friendships are much harder.
Ditto, which is why I didn’t click that option. I also meet a lot of my friends from bars. Not singles bars where we put on high heels and eyeliner specifically for the purposes of reeling someone in. Just a regular bar where you hang out with your friends, and talk about the news.
Realized I’d forgotten to answer my own poll. Heh.
The vast majority of my relationships/flings came from people who were friends first, or at the very least if not close friends then among my circle-of-people-I-socialize-with. A very few have been people who I was introduced to by friends or circumstance and we ‘clicked’ immediately, and began dating/fooling around without an intermediary friendship. (Most of these were fellow Ren Faire workers, because it’s like that there.)
I have never given my phone number to a stranger, nor picked up/been picked up at a bar.
Oni no Husband and I met at work; he was a new hire and I was barely a supervisor but not management. We started talking the first day, and became friends, and there was serious chemistry but both of us were in (bad) relationships. As soon as we could both extricate ourselves therefrom, we started going out. (OK, I will admit to some smooching/necking before singleness was achieved. But we were still pretty good about it.)
–Oni no Maggie