Interleukin 17A is a key effector cytokine in numerous chronic inflammatory diseases. Its neutralization is therapeutically effective and approved in the treatment of chronic inflammatory conditions. Recently, five additional members of the IL-17 cytokine family have been identified, which also contribute to chronic inflammation. Innovative therapeutic strategies therefore aim to simultaneously block not one, but several members of this cytokine family in order to further increase therapeutic efficacy. This article reviews the current knowledge regarding the role of the IL-17 cytokine family in chronic inflammation.