A variety of cancers are associated with bone. Primary tumors can arise in bone, common cancers, such as those of breast and prostate origin, metastasize to bone, and multiple myeloma neoplastic disease affects bone profoundly. The cellular and molecular mechanisms underlying these pathological processes are increasingly being understood. The interaction of tumor cells with bone cells, osteoblasts and osteoclasts, and with the bone local environment is a new promising direction in research, which should help to develop new therapies. In this article we will relate the newest developments in the molecular research to the pathology of the tumor bone disease. Potential new targets for drugs, aimed specifically at tumor bone diseases, will be highlighted. Furthermore, we will describe the existing compounds that are either used in treatment or have a potential as therapeutic agents, such as bisphosphonates, Src inhibitors, and selective estrogen receptor modulators.