The Older Persons and Informal Caregivers Survey Minimum DataSet (TOPICS-MDS) is a public data repository which contains information on the physical and mental health and wellbeing of older persons and informal caregivers across the Netherlands. The database was developed in part to ensure uniform collection of outcomes measures, thus promoting comparability between studies. To date, 60 different research projects have contributed data to this initiative, resulting in a pooled dataset >43,000 older persons and >9,000 informal caregivers.