This is a perennial question on the internet. The answer is yes, if the underlying laminate surface is bonded securely, you can glue directly to it. In short, you need to sand the old surface, wipe it down with a solvent, and use a solvent based contact adhesive. Another approach (and the one I preferr) is to air staple a layer of 1/4in. lauan plywood over the old counter and edges and then glue the new laminate to that. Both of these approaches are discussed in a chapter of my Taunton Press book, "Making Plastic Laminate Countertops". The book can be viewed at their website- www.taunton.com. I'll be glad to answer any specific questions here or you can e-mail me.