yes and no. You might hear a lot of people that say they have been building pcs forever and have never used one and never been the victim of ESD so you don't need one. You can get away without using one and decrease your chance of experiencing ESD by: build on wood or tile floors (avoid building on carpet), always touch something metal like the case or powersupply before you handle any hardware (this will discharge any built up charge), and keep furry animals away from where you are building (I had one builder tell me that cats are little walking static death bombs lol). I personally use one just to be on the safe side. It was only 5 bucks.