Humans & their predecessors have been sewing clothing from cut-out pieces of hide or cloth for perhaps 250k - 500k years. There must be some part of mathematics that deals with pattern parts & how they sew together to form 3D surfaces. Most clothing materials are flexible, but more-or-less flat. The only way to generate a 3D curved surface is by sewing the parts together in complex ways. I'm particularly interesting in trousers -- especially those for athletic endeavors (biking, running, rowing). The idea is to develop clothing that doesn't bind, but also has seams in places that aren't going to rub your skin raw. Any of you who have ridden bicycles in "street clothes" will know precisely what I mean. While an undergrad at MIT, I used to ride my bike upwards of 7 miles each way in Levis jeans, which used to have _rivets_, including one in a particularly sensitive location, which you could also appreciate by standing too near a campfire. The only saving grace was that I rode most of the way standing up. I've recently had difficulty finding athletic clothing that _doesn't_ have seams in the wrong places. I'm wondering if the problem is mathematically insoluble -- perhaps the design of trousers requires seams that end up in the wrong places. Can anyone on math-fun provide pointers to the appropriate mathematical literature? Thanks in advance.