The treatment assignment is based on the presence or absence of an HLA-identical sibling donor (Genetic Randomisation, NOT formal Randomisation). Patients with suitable HLA-identical sibling donors are offered a tandem transplant approach consisting of standard autografting nonmyeloablative radiotherapy and allografting. Patients without HLA-identical siblings are treated with standard double autologous transplantation as per Institutional guidelines or enrolled in other treatment programs approved by local IRBs.This is a multi-center study. The Division of Hematology of University of Torino at the S.G.B. Hospital, Torino, Italy, is the co-ordinating Center.

Inclusion Criteria:

• Durie-Salmon stage IIA-IIIB multiple myeloma;
• Age > 18 and ≤ 65 years;
• previously untreated myeloma;
• presence of a sibling (potential donor);
• bilirubins < twice normal;ALAT and ASAT < four times normal;
• left ventricular ejection fraction > 40%;
• creatinine clearances > 40 mL/min;
• Pulmonary dysfunction with diffusing capacity for carbon monoxide (DLCO) > 40% and/or need for continuous oxygen supplementation;
• Karnofsky performance status > 60%;
• patients must give written informed consent;

Exclusion Criteria:

• Age > 65 years
• previously treated myeloma;
• absence of a sibling (genetic randomisation cannot be applied);
• Karnofsky performance status score < 60%
• HIV-infection;
• pregnancy;
• Refusal to use contraceptive techniques during and for 12 months following treatment
• patients unable to give written informed consent

PS. Informed consent is obtained from each patient according to the Institutional Review Boards of the participating centers. The study is conducted according to the Declaration of Helsinki.