Ever wonder why Jessica Alba's butt looks so super fine in denim? Her secret is Rich & Skinny jeans. We recently got a chance to speak with Rich & Skinny designer, Joie, who gave us some insider advice and more celeb denim dirt.

Here are some of the seasons best denim tips straight from Joie.

• Hottest Denim Trend: Our "Boyfriend" (ala Katie Holmes and Reese Witherspoon) is the hottest jean right now.

• Best Classic Cut: Our "Sleek" style (favored by Blake Lively and Jessica Alba), a low rise slim leg, is a good place start.

• Which celebs love Rich & Skinny: Blake Lively and Jessica Alba love our most popular "Sleek" style and Hilary Duff loves our "Lanky" jeans.

• How stars are styling their Rick & Skinny's right now: We've seen pairing with ankle boots, our "super skinny" style tucked into boots, and sexy, silk tops with our rinse wash for night-time drama.

• Joie's favorite Rich & Skinny stars: For Fall 2008, the Best Rich & Cool Dude is Richard Branson and the Best Rich & Fit Babe is Cameron Diaz.