Multiple myeloma (also known as myeloma or plasma cell myeloma) is a progressive hematologic disease. It is a cancer of the plasma cell, an important part of the immune system that produces immunoglobulins (antibodies) to help fight infection and disease. Multiple myeloma is characterised by excessive numbers of abnormal plasma cells in the bone marrow and overproduction of intact monoclonal immunoglobulin or Bence-Jones protein. Hypercalcemia, anaemia, renal damage, increased susceptibility to bacterial infection, and impaired production of normal immunoglobulin are common clinical manifestations of multiple myeloma. It is often also characterised by diffuse osteoporosis, usually in the pelvis, spine, ribs, and skull. This new book gathers the latest research from around the globe on multiple myeloma research and related topics such as immune defects in multiple myeloma, surgical options in the treatment of spinal myeloma, the role of PBSC in multiple myeloma and allogeneic stem cell transplantation.