Primary malignant tumours of bone and soft tissues (sarcomas) arise from cells of the mesenchymal lineage. Bone and soft tissue sarcomas are rare compared to more common cancers, but nevertheless they represent a significant clinical problem in terms of diagnosis and treatment. Secondary tumours from primary cancers of solid organs such as breast, lung and prostate, frequently metastasise to bone and represent the most common malignant tumour of bone. In addition, haematological neoplasms, such as myeloma and lymphoma, commonly involve bone. Several groups at NDORMS are actively studying genetic, epigenetic and molecular mechanisms underlying the pathogenesis of these primary and secondary malignant neoplasms. In addition the role of the immune system, tumour vascularity and micro-environment on growth and spread of these neoplasms is being defined with a view to developing novel and effective therapies for these primary and secondary malignant tumours.