Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of disorders in which chronic inflammation of the skeletal muscle, leading to muscle weakness, is a common feature. Different phenotypes have been identified within the IIM spectrum based on extra-muscular manifestations, immunology, muscle histology, responsiveness to therapy, and prognosis. The pathogenesis, classification, treatment, and prognosis of the different IIM subtypes are subject to active discussion and research. This review highlights the most relevant literature published on this topic over the last year.