In the light of sustainability and Green Chemistry, mechanochemistry offers fast reactions in a solvent-free environment. Mass productivities often exceed the solvent-based reaction equivalents, and the work-up procedures are generally easier. Beside thermal, electrochemical and photochemical energy supply, a less known form of mechanochemistry is based on energy input by impact and shearing forces; typically ball mills are used to conduct those reactions. This article gives examples how mixer mills and planetary ball mills are successfully used to conduct mechanochemical processes.