This phase I study is designed to select patients with refractory and intractable disease. SLE patients with impaired visceral organ function and chronic exposure to glucocorticoid therapy are complicated by significant morbidity, frequent hospitalizations and high-risk of mortality. For participants in whom the indication is nephritis, active disease must be present despite at least 6 cycles of monthly pulse cyclophosphamide. Participants with extra-renal lupus need to fail 3 months of monthly cyclophosphamide. Patients who have an HLA matched sibling, will be offered allogeneic HSCT. Because of high transplant related toxicity and mortality in conventional myeloablative regimens, we will utilize a mini-conditioning regimen. To minimize GvHD, candidates must be 50 years old or younger and in vivo CAMPATH will be used in the conditioning regimen to deplete infused donor lymphocytes.