The dossier of documents traced in the Archivio del Capitolo di San Pietro includes some new findings on Gian Lorenzo Bernini’s activity in the Vatican Basilica between 1624 and 1633. The first concerns the Baldacchino, and consists in the original contract for «l’opera delle Colonne a ornamento sopra l’altare di detti SS. Apostoli», entrusted to Bernini, who is cited in the document in question as «scultore Soprintendente». The agreement enables us to elucidate Bernini’s method of working and attests to the many obstacles that the artist has to overcome in the realization of the gigantic structure. This is confirmed by a passage relating to the wages to be established for his assistants (Laurenziani, Albrizzi, de’ Rossi, Beltramelli and Lucenti): it cites the difficulties that the artist had to confront and that complicated, or precluded, his ability adequately to estimate in advance all the costs, in view of the unprecedented nature of the commission. The same indecision also regarded the retribution of Bernini himself: an initial fee of one hundred scudi per month mushroomed into the subsequent 250 scudi per month for a total of 34,000 scudi: an exorbitant figure for the period. To this remuneration should be added the 10,000 scudi donated to him in 1633 by Urban VIII, who was particularly pleased by this work. The documents further show the relation of trust and esteem that was established between Bernini and the Barberini Pope, as suggested by another passage in which the Pope intimated to the cardinals that the artist should be granted all the fees due to him according to the results achieved up till that date. Other new findings regard the artist’s work on the crypt of the ‘Confessio’, more difficult to reconstruct. The difficulties arise from the impossibility of identifying the two silver gates («due sportelli d’argento») mentioned in the (unpublished) order for payment with the existing railing of the ‘Confessio’, which is not of silver but of gilt bronze. It should be noted, however, that this railing shows signs of having been further embellished in the first decades of the seventeenth century, in particular by the addition of heads of angioletti, which can be associated with Bernini’s style. If what is mentioned in the order for payment does not correspond in detail to the existing cancellata, it is still valuable since it testifies unequivocally to the fact that, during his interventions in the crossing of St. Peter’s, Bernini was also commissioned to furnish decorations for the ‘Confessio’ below.