This portrait was formerly attributed to Rembrandt, from whose style it derives and whose false signature it bears. There are several pentimenti (alterations made by the artist to an area already painted). The attribution to Willem Drost, one of Rembrandt's pupils between 1650-54, has been made based on comparisons with other works by him. Probably executed about 1653.
The National Gallery, Trafalgar Square, London WC2N 5DN