For a successful haploidentical transplant is necessary to overcome the HLA barrier. We present our experience using high dose of unmanipulated CD34, in vivo T cell depletion and a RIC regimen. After a signed inform consent seventeen patients received 20 transplants (3 ptes. underwent a second haplo transplant after engraftment failure of the first). 9 were women, median age was 17.3 years (7-36), 40% were under sixteen. 5 patients had high risk AML CR1 or CR 2; 3 had high risk ALL CR1 or CR3; 5 heavily transfused Fanconi anemia,1 aplastic anemia,1 myelofibrosis, 1dendritic cell leukemia CR2, 1 hemophagocytic linphohistiocytosis. Two patients received the haplo transplant after an unsuccessful cord blood transplant. The donors were 16 mothers, 3 siblings and 1 father. 80% had 3 out of 6 match. The conditioning was cyclophosphamide 2000 mgs/m2, fludarabine 120 mgs/m2 +/- thiothepa 5 mgs/kg. In 11 procedures TBI 200-400 Cgy was added. In vivo T cell depletion was done with Alemtuzumab 0.2 mg/kg/day from day -4 to cero. All patients received unmanipulated peripheral blood CD34 obtained by apheresis (median 12 mill/kg) in 2 cases bone marrow was added. The GVHD prophylaxis was accomplished with CyA for 180 days and MMF for 30. Filgrastim was administered from D+6 until neutrophil recovery. Neutrophil engraftment occurred at median of 11 days (9-14) in 82% of the patients after first transplant and in 100% after the second, 1 patient had a secondary graft failure. The incidence of acute GVHD GI-II was 25%, there were no cases of GIII-IV. One patient had aGVHD GIII after DLI, chronic GVHD was presented in 40% of the patients, in all cases limited, and in 50% of them treated with only topical medication. The 100 days mortality was 17.64 % and with a median follow up of 16 months (1-38) the overall survival was 53.5%. The strategy of use high dose of unmanipulated CD34, in vivo T cell depletion and a RIC preparative regimen produce a reliable engraftment, low incidence of GVHD, low day 100 mortality and good overall survival in this high risk group. It deserve more studies.