"I'm not aware of any other technique that does that." Well, as pointed out by others, TDD doesn't actually prove that. There are however methods that do, whi

"I'm not aware of any other technique that does that." Well, as pointed out by others, TDD doesn't actually prove that. There are however methods that do, which fall under the general heading of formal methods or program proof. Read "A Discipline of Programming" by Dijkstra for a reasonable introduction. The techniques work, but are laborious. Modern theorem provers can help, but it still involves considerable effort. Which implies that such methods likely won't provide a return on investment unless the cost of errors in the program is extremely high (avionics, medical control). I prefer to think of TDD as similar to working a problem backwards and forwards in elementary algebra. You may still have gotten the answer wrong, but you'll have to have made a mistake twice, so it helps your odds quite a bit.