In older persons, the combination of osteopenia/osteoporosis and sarcopenia-known as osteosarcopenia-has been proposed as a subset of frailer individuals at higher risk of institutionalization, falls, and fractures.The pathophysiology of osteosarcopenia is the consequence of a complex set of interactions between bone, muscle, and fat.Osteosarcopenic patients have very particular clinical, biochemical, diagnostic, and functional characteristics that could be identified in clinical practice.In addition, new therapies targeting both muscle and bone, which involve fat as a new target, are being developed.In this session, the pathophysiology of osteosarcopenia will be reviewed.In addition, a clinical definition of osteosarcopenia aiming to describe the clinical, functional, and biochemical features that are unique to these patients will be presented.The use of imaging combined with functional assessments for the diagnosis of osteosarcopenia will be discussed, including novel methods to quantify bone marrow and intramuscular fat.In addition, we will analyze preventive measures and therapeutic interventions that can benefit both muscle and bone simultaneously.We intend to go over the translational aspects of sarcopenia and osteoporosis research and highlight expected outcomes from different interventions for both conditions.