In case anyone isn't aware of the nuances of color theory (I definitely wasn't), here's a link to a site with a great explanation of what the different color harmonies are http://www.tigercolor.com/color-lab/color-theory/color-harmonies.htm
In pretty much every single color harmony described, you're supposed to let one color dominate. I thought it might be a cool idea to use these color harmonies in a way that an outfit is composed of various shades of a single dominant color, while the background (perhaps just a solid color?) is composed of the harmonious color(s). I think a good example of what I'm trying to get at is the picture Danish posted below of the red and yellow bunching bags against the green backdrop. The photos David posted of the models against the yellow backdrop are also good examples of what I'm trying to express (I like the idea of largely monochromatic outfits).