Thalidomide has recently emerged as an effective treatment for patients with myeloma refractory to conventional chemotherapy. So far only limited experience is available on thalidomide for newly diagnosed myeloma. Therefore the Nordic Myeloma Study Group decided to perform a trial comparing traditional melphalan-prednisone therapy with melphalan-prednisone + thalidomide/placebo. The study design is a multicentre double-blind randomised placebo-controlled trial. Mainly patients >65 years of age will be included since patients <65 years will be treated with high dose chemotherapy with autologous stem cell support. The primary end-point is overall survival. Secondary end-points are quality of life, response rate, time to response, response duration and toxicity.