The Collegiate Church of St Mary, Dumbarton, Scotland, was founded in about 1453 by Isabella, Countess of Lennox and Duchess of Albany. During the medieval period, collegiate churches took on the responsibility of caring for the sick and elderly within their parishes. St Mary's met these needs in a hospital attached to the main church building, and a separate leper house located at a "safe" distance from the town centre. The church ceased to exist at some time during the Scottish Reformation of the mid-sixteenth century.