Rumble in the Jungle

So, one of my goals here on Slushe is to get more familiar rendering with iray. I previously worked with 3Dlight, and that was great, but I think there is more potential with iray. However, I keep running into this problem with noise. The more items I add to a scene, the more noise comes out in the final render. Any advice out there about how to reduce this for the final product? Thanks!