The workshop of a Renaissance artist was both studio and school, where apprentices were trained to paint in the style of the master. Since large commissions required the efforts of many painters, backgrounds, still-life details, and secondary figures were often painted by assistants. A master might also give lesser commissions entirely over to his assistants, simply approving the work as meeting his standard. It is often difficult to distinguish the work of the master from that of talented assistants whose individual styles were not yet fully developed.