Treatment of older adults with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) is challenging because of disease morbidity and associated treatments. Both diseases represent a genetically heterogeneous group of disorders primarily affecting older adults, with treatment strategies ranging from supportive care to hematopoietic stem-cell transplantation. Although selected older adults can benefit from intensive therapies, as a group they experience increased treatment-related morbidity, are more likely to relapse, and have decreased survival. Age-related outcome disparities are attributed to both tumor and patient characteristics, requiring an individualized approach to treatment decision making beyond consideration of chronologic age alone. Selection of therapy for any individual requires consideration of both disease-specific risk factors and estimates of treatment tolerance and life expectancy derived from evaluation of functional status and comorbidity. Although treatment options for older adults are expanding, clinical trials accounting for the heterogeneity of tumor biology and aging are needed to define standard-of-care treatments for both disease groups. In addition, trials should include outcomes addressing quality of life, maintenance of independence, and use of health care services to assist in patient-centered decision making. This review will highlight available evidence in treatment of older adults with AML or MDS and unanswered clinical questions for older adults with these diseases.