MAC is a powerhouse cosmetics brand backstage at fashion shows–they currently participate in 23 global Fashion Weeks and have provided the makeup looks at some 850 shows worldwide–200 of those are in the Big Four fashion capitols. The brand also incites a lot of lust in makeup junkies because of the rich pigments, high-wattage ambassadors (Lady Gaga! NIcki Minaj!), and killer collaborations. (We were begging–nay, pleading–for more information about the Gareth Pugh and Daphne Guinness collabs launching in early winter, only to be teased with, “They will blow you away!” Duh.)

We had the chance to to do a Q and A with Gordon Espinet and Jennifer Balbier, two senior VPs at MAC, and to hang around backstage with their makeup artists at the Alexander Wang, Jason Wu, and Altuzarra shows. What we learned is that being a brand like MAC is a bit of art and science.

To give you an idea of the scope of runway shows, Espinet told us that makeup artists use 10 to 12 mascaras per show. Multiply that by 200 shows, and you need 2,000 to 2,400 mascara tubes per season. So you better have product that can handle the volume and the intensity–think bright lights and avant garde makeup looks.

The cool thing is that MAC uses runway shows to test out new products that haven’t hit the consumer market yet. Sometimes it results in a winner, like the brand’s Matchmaker Foundation SPF 15; it was developed after artists complained they didn’t have a foundation that looked “lifelike,” Balbier told us. Matchmaker was trialed at the fall 2011 shows at Prabal Gurung and Monique Lhuillier, among others, and was a hit, particularly because of the number of very light skinned Eastern European and Russian models. Another runway-tested product to look out for this fall is the Pro Longwear Eye Shadow, part of the Styledriven collection which launches September 22.

Sometimes things don’t work out, though. Balbier told us that MAC used a longwear mascara backstage that was so longwearing, the models couldn’t remove it to go to their next show. MAC ended up marketing it to women who live in a hot and humid climate, but it did not work backstage.

And what about this season? As I creeped around backstage, I learned about a few products we can expect to launch next spring. At Jason Wu, there was Scarlet Ibis lipstick–top it with some neon orange pigment to get the look of the show. At Peter Som (see the look at right), Young Venus in Extra Dimension eye shadow and Innocence, Beware! lipstick gave the girls that dreamy look.

With a little bit of tweaking, the runway actually can be reality.