This study looks at using a *reduced-intensity conditioning* (RIC) method for patients with non-cancerous diseases who need a stem cell transplant. **Hematopoietic stem cell transplant (HSCT)** is when healthy cells from a donor are used to replace diseased cells in the body. The goal of RIC is to use lower doses of chemotherapy to prepare the body, which may lead to fewer side effects and better overall health outcomes than traditional methods. **Umbilical cord blood transplant (UCBT)**, **bone marrow transplant (BMT)**, and **peripheral blood stem cell transplant (PBSCT)** are all methods we are evaluating. **Key Points:** - Participation involves regular follow-ups to check for graft success and side effects. - No financial compensation is provided for joining the study. - RIC aims to reduce damage to organs compared to standard treatments. Joining this study may offer the chance of better recovery with fewer health risks. However, it's important to consider that no financial help is offered for joining, and regular medical check-ups are required.