With sanforized jeans, none. With raw jeans about an inch in the waist and an inch in the inseam. You will get the leg riding up a little after a few weeks of wear, this is caused by heavy denim creasing behind the knees.

BUT, all jeans will stretch with wear, depending upon how much pressure is put on the waist band, you can get up to 1.5" stretch after being worn for a time. For a discussion on stretching, take a look here.

Jackets, shirts and t-shirts are generally one-washed, so any shrinkage should be minimal, but please read the notes on the product web page as any possible shrinkage for that specific item will be explained there.