Falls, fractures, frailty, osteoporosis and sarcopenia are highly prevalent in older persons. While the concept of osteosarcopenia is new, it is a rapidly evolving and cross-disciplinary problem. Prevention and treatment are challenging and a combined therapeutic approach is needed. Osteosarcopenia provides evidence-based information on how to prevent and treat these conditions at multiple settings, including multiple illustrations, care pathways and tips to easily understand the pathophysiology, diagnostic methods and therapeutic approach to these conditions. This work evaluates the potential for a link between osteoporosis, sarcopenia and obesity.- Presents diagnostic and therapeutic tips that facilitate the design and implementation of new care pathways, impacting the wellbeing of our older population- Provides cross-disciplinary understanding by experts from the bone/osteoporosis field and the muscle/sarcopenia field- Covers muscle and bone biology, mesenchymal stem cells, age-related changes and cross-talk between muscle, fat and bone, falls and fracture risk, glucose metabolism, diagnosis, imaging, and genetics of osteosarcopenia