Magnetic Resonance Imaging (MRI) is a key tool to evaluate soft-tissue tumors in different phases of the diagnostic flow-chart. MRI is the key imaging tool for the assessment of undetermined deep-seated soft-tissue masses. MRI features can provide information that help in the recognition of clearly benign conditions versus neoplasms that need further examinations and referral in specialized sarcoma centers. After a diagnosis of soft-tissue sarcomas (STS) MRI provide fundamental elements to plan surgery and improve patients’ prognostication. In the future, the implementation of more accurate quantitative MRI applications are expected to improve patients’ care with the goal of a personalized medicine, even in patients with rare tumors such as STS. In the current chapter, we will discuss the role and possibilities of MRI in different diagnostic steps of patients affected by soft tissue tumors. The information provided have the goal to be helpful in clinicians involved in the care of these patients, including Musculoskeletal Radiologists, Oncologic or Orthopaedic Surgeons, and Oncologists.