When H&M announced its latest designer collaboration with Maison Martin Margiela, we’ll admit we were a little surprised. Margiela is so avant-garde, so cult-y, and with little name recognition (OK, more than a little thanks to Kanye) we’d have figured them the last brand to do a collaboration with a mass retailer. But then again, H&M got Karl Lagerfeld to do a line for it in 2004, and then, somehow, the retailer convinced the most reclusive and enigmatic of designers, Rei Kawakubo, to do a Comme des Garcons collaboration in 2008. So maybe it’s not so surprising that Maison Martin Margiela is doing a mass collab–maybe it’s even obvious. It seems like every major designer has done a lower-priced collaboration with any number of mass retailers recently.

Over the past five years, we’ve tirelessly and breathlessly documented every designer collaboration as it has dropped. It was exactly the kind of fashion we could get behind. High fashion from our favorite designers (like Marni, Pierre Hardy, Lanvin and Proenza Schouler just to name a few) at prices we could actually afford. Accessible fashion–it was real! It built hype! Like camping-out-in-line-in-the-freezing-cold-for-days kind of hype! After Karl Lagerfeld for H&M in 2004, Target pioneered a series of designer collaborations under its “GO International” program, which kicked off in 2006 and ended just last year. The “GO” series made household names of young, seriously talented designers like Rodarte, Proenza Schouler, Luella Bartley, and Tracy Feith long before Michelle Obama did. It saw shoppers essentially looting their local Targets for these prized limited edition collections, and, correspondingly, saw the creation of the eBay poacher. I still wear a Proenza for Target cardigan, and Cheryl’s Pierre Hardy for Gap wedges still get her compliments on the subway.

And although Target has ended their GO International program, everyone else, it seems, has picked up where it left off. Macy’s has enlisted Karl Lagerfeld, Giambattista Valli and Alberta Ferretti to design for its contemporary Impulse line. JCPenney has had success with Charlotte Ronson and hopes to entice shoppers with new collabs with Marchesa and William Rast. The list could go on and on. Like, really on and on, because there have been so many. But today, in chronological order, we’re bringing you the 20 most important, most hyped and, well, most awesome.

Do you agree with our list? Which were your favorite designer collaborations so far?