High-dose therapy with autologous stem cell therapy (ASCT) has become the treatment of choice for eligible patients with myeloma. We analysed retrospectively the prognostic influence of pre-transplant characteristics and transplant modalities on response and survival in 211 myeloma patients who were transplanted in our centre between 1994 and 2004. All patients received peripheral blood stem cell support after conditioning with melphalan alone (183 patients), or melphalan and total blood irradiation (28 patients). We evaluated the influence of age, type of multiple myeloma, status prior and post ASCT, previous treatment regimens, time of ASCT from diagnosis, year of autograft, dose of re-infused CD34(+) cells, plasma cell infiltration and beta2-microglobulin at diagnosis on overall survival (OS) and event-free survival (EFS) to define patients with better prognosis. Median OS and EFS from transplantation were 50.9 and 20.1 months, respectively. Median OS from diagnosis was 68.8 months. Transplant-related mortality was 1.4%. Lower beta2-microglobulin levels, achievement of complete remission (CR) post transplant and lower plasma cell infiltration at diagnosis and transplant correlated with longer EFS and OS, whereas CR at transplant and low international prognostic index at transplant correlated with better EFS. Higher CD34(+) cell dose correlated with improved OS. We conclude that ASCT is safe and effective and the outcome is independent of age, time from diagnosis, previous treatment and conditioning regimen.