Dyneins are a class of microtubule (MT)-based, cytoskeletal motors that are found in two forms: cytoplasmic and axonemal. Dyneins transport cellular cargoes toward the MT minus-end by converting chemical energy in the form of adenosine triphosphate (ATP) to mechanical work. Dyneins are involved in a variety of cellular processes, including cell motility, mitosis, axonal transport, and developmental patterning. The dynein heavy chain is repurposed for accomplishing these tasks through the recruitment of a variety of accessory proteins. Cytoplasmic dyneins fulfill roles in mitosis, cellular cargo transport, and intraflagellar transport (IFT), while axonemal dyneins are responsible for the flagellar and ciliary motility.