INCLUSION CRITERIA:  To be eligible to participate in this study, an individual must meet all of the following criteria. Subjects and their family members who undergo screening but ultimately do not meet criteria for cohorts 1-5 will be removed from the study. Subjects may forgo screening and sign directly onto cohorts 1-5 if they meet criteria based on either prior NIH testing or external examinations. Family members will only be asked to be screened for participation onto this study after confirmation of eligibility by an affected participant.  Cohorts 1-4  Age >=2 years Diagnosis of acquired or inherited bone marrow failure or ineffective hematopoiesis or TBD (see below for cohort 3 specific criteria) Ability and willingness to come to the NIH CC for consultation and testing Ability of subject or Legally Authorized Representative (LAR) to understand the investigational nature of the protocol and their willingness to sign a written informed consent document. For cohort 3 - TBD:  Presence of a pathogenic, likely pathogenic, or known family mutation in a telomere maintenance gene  OR  If mutation negative or VUS, telomere length <10^th percentile in lymphocytes with at least two clinical features: 1) cytopenia (Hb <10g/dL or ANC <1.5x10^9 or platelets<100), 2) documented liver fibrosis by histology OR abnormal liver US / fibro scan consistent with fatty liver or fibrosis), 3) documented pulmonary fibrosis by histology /  Cohort 5  Age >= 2 years First degree family member with a known or suspected inherited bone marrow failure syndrome from a patient enrolled on this or another NIH protocol as determined by a PI  or AI  Ability and willingness to safely provide blood, buccal swab, or fibroblasts for testing as stated by subject Ability of subject or Legally Authorized Representative (LAR) to understand the investigational nature of the protocol and the willingness to sign a written informed consent document.  EXCLUSION CRITERIA:  Post HSCT (except if cohort 3 - TBD) MDS/AML on chemotherapy (patients with hypoplastic MDS who have received or are on erythropoietin stimulating agent (ESA), granulocyte colony-stimulating factor (GCSF), or immunosuppressive treatment will not be excluded). Subjects in Cohort 3 with TBD can be seen if they have received chemotherapy for MDS/AML.