The assessment and treatment of patients with idiopathic inflammatory myopathy has taken a major step forward over the past few years. Through the efforts of multi-disciplinary international groups of experts interested in the management of patients with myositis, initiatives have led to the development of a core set of outcome measures critical to their assessment. Similarly, the lack of consensus on several issues of clinical trial design has been addressed resulting in the development of a definition of clinical improvement for adult and juvenile patients with inflammatory myopathy using the core set outcomes. The final step in the puzzle of well-designed therapeutic trials in myositis is the determination of consensus guidelines to conduct such trials in adult and pediatric populations of myositis patients.