Depends on how you're going to quilt it, and the size of the beads I would guess! If it's a machine quilting job, I'd finish the quilting and then do all the beading. Rather not take a chance on snagging a bead, or breaking either a bead or the machine needle. On my hand quilting projects I've added beadwork before the backing/batting/basting and then gone right ahead with the hand quilting. I've only used small beads, tho. That was no problem with either the quilt frame or hoop.