Paintings can be divided into three categories: those he painted by himself, those he painted in part (mainly hands and faces), and those he only supervised. He had, as was usual at the time, a large workshop with many apprentices and students, some of whom, such as Anthony van Dyck, became famous in their own right. He also often sub-contracted elements such as animals or still-life in large compositions to specialists such as Frans Snyders, or other artists such as Jacob Jordaens.