The music of Gregorio Allegri (1582-1652) falls in many respects between that of Palestrina and Lotti. His famous Miserere is a simple setting of the penitential Psalm 50 (51). His polyphonic setting alternates with the chant, which would customarily have been used, in this case a simple monotone, reflective of the solemn nature of the occasion. This Psalm would have been performed at the end of the Tenebrae services of Holy Week at the papal chapel. It would have been sung in complete darkness while the pope and cardinals knelt before the altar. Allegri’s setting, which may date from 1638, has had a checkered history. The papacy refused to allow any copy to leave the chapel, realizing that they were in possession of a work of considerable renown. There is a story that it was Mozart who first broke this barrier of secrecy by copying the work out from memory. Whatever the truth of this, there developed several versions of the piece in manuscript sources, which show how the added ornamentation changed over the years. Whereas usually in the papal chapel, such added ornamentation would have changed from performance to performance, in the case of this work, because it was sung in darkness, the embellishments – though elaborate – were memorized and were thus recorded on paper. This did not prevent changes occurring later in its history, and the version heard today is based on a sketch made by Mendelssohn of the ornamentation. It is the case that this is hardly what would have been heard in Allegri’s own time, but it is also true that music takes on its own life when it leaves the hands of its creator: thus Allegri’s Miserere and the present tradition of performing this version.