Niccolò di Buonaccorso was one of the most accomplished Sienese painters of the second half of the fourteenth century, though he is little known today. His surviving works are small in scale and rendered in a highly refined miniaturist technique. This richly decorated "Coronation of the Virgin" is one his most important works. It corresponds in style, size, and framing to two other panels also depicting scenes from the Life of the Virgin. The three panels may have formed part of a portable polytych for private devotion, or a "custodia" (portable tabernacle) containing a sculpted statuette of the Virgin and Child. The backs of all three panels are decorated with the same ornamental pattern, suggesting that the structure originally folded in a fashion that would have allowed the backs to be seen.