Genetic deletion of Myostatin, a member of the Transforming Growth Factor-beta family of signalling molecules, resulted in excessive growth of skeletal muscle. It demonstrated the remarkable intrinsic growth potential of skeletal muscle and led to the proposal that growth stimulation could amend diseased muscle without having to correct the primary cause of the disease. Furthermore, the presence of Myostatin in skeletal muscle in a number of muscle diseases and disease models suggested that it aggravated the primary pathology. Inhibition of Myostatin activity in mdx mouse, the animal model for Duchenne muscular dystrophy, resulted in increased force production and better tissue architecture which implicated Myostatin as a target for new therapeutic strategies. In this review we will discuss the phenotypes of animal models in which Myostatin function is altered. We will highlight the particularities of the Myostatin signalling pathway and describe molecular strategies that have been developed to inhibit the function of Myostatin on muscle. Finally, we will summarise the role of Myostatin in diseased muscle and discuss blockade of Myostatin as a potential therapy for muscular dystrophies.