Every year new people join the various businesses that use mixing machines in their laboratories and manufacturing facilities. What seems obvious to many experienced personnel can be complicated and frustrating to these newcomers. The purpose of this guide is to present a fundamental explanation of the “what, how, when and why” about high-speed dispersers. This guide is dedicated to those newcomers who will become the experts of the future. A disperser is a type of mixer used to rapidly break apart lumps of powdery material, uniformly distributing and wetting them in a liquid. It is also used to dissolve soluble solids in a liquid. A disperser works on the principle of energy transfer. A disc-type blade is mounted at the bottom end of the mixing shaft and rotated at a relatively high tip speed. (Tip speed is the speed at the outer tip or edge of the rotating disc. Tip speeds typical of dispersers are measured in feet per minute, calculated by multiplying the constant 3.14 times the diameter in feet of the disc times the revolutions per minute of the mixing shaft.