I. Introduction II. Corticosteroid Receptor Properties A. Corticosteroid receptor diversity in brain and pituitary B. Access of corticosteroids to brain receptors C. Expression of MR, GR, and receptor variants D. Regulation of transcriptional activity E. Conclusion III. Molecular and Cellular Effects of Corticosteroids in Hippocampus A. Intrinsic cell properties B. Amino acid transmission C. Aminergic transmission D. Chronic absence of corticosterone E. Chronic exposure to high corticosteroid levels F. Conclusion IV. Role of Corticosteroid Receptors in the Central Stress Response A. Corticosteroid receptors and HPA control B. Role of hippocampus in HPA regulation C. Behavioral effects involving hippocampal MR and GR D. Glucocorticoid feedback resistance and supersensitivity E. GR knockouts F. Conclusion V. Implications for Age- and Stress-Related Brain Disorders A. Role of genotype B. Impact of early life experience C. Corticosteroids and affective disorders D. Aging, neurodegeneration, and age-related diseases E. Conclusion VI. Summary