There are important differences between performing research in geriatric medicine and in other fields of medicine. Geriatric research requires specific preconditions in all phases of conducting research due to the heterogeneity among geriatric patients and the high prevalence of multi-morbidity, often resulting in impaired physical, psychological and social performances. This paper discusses issues important for successful recruitment and selection of subjects, the informed consent procedure and selection of appropriate research designs and research instruments in geriatric research. The recommendations given are based on a review of relevant literature and own research experiences in the 'Nijmegen geriatric research programme on Brain Failure'.