To examine and describe psychological outcomes in long-term (> 5 years) survivors of allogeneic bone marrow or stem cell transplantation (SCT) in childhood. This will be conducted in a one-time cross-sectional assessment using both performance based measures and survey questionnaires. Comparisons will be made to established normative data on well validated standardized instruments and to control participants in the community without a history of serious illness, matched on age, gender, race/ethnicity and socioeconomic status.