The Primo Libro di Madrigali a quatro voci was, chronologically speaking, the second work that Giovanni Pierluigi da Palestrina published. It was printed in 1555 in Rome by the publishers and printers Valerio and Luigi Dorico. On the title page the composer refers to himself as «Cantore nella Cappella di N[ostro] S[ignore] », a title which in Rome at that time represented the highest position to which a musician might aspire. Pierluigi’s appointment as cantore pontificio officially took place on 13 January 1555 following the explicit wishes of Pope Giulio III, his benefactor. «absque ulo [síc] examine [ ... ] et absque consensu cantorum ... »: the pontiff had thus imposed this decision upon the Collegio dei cantori, disregarding the rules set down by the Constitutiones of the chapel and overriding the norms which he himself had established in the Motu proprio of 5 August 1553. The precise date of publication of this work is unknown, but the information on the title page, as well as a series of events which took place in the first half of that year, allow us to restrict the period.