Information was at the heart of the ransoming of captives in the early modern Mediterranean. The living merchandise exchanged - captives - was to some extent constituted and its price defined through the collection of information from different sources, mainly for financial reasons: the captives and their relatives had to contribute to the ransom. The identification process implemented by the Roman "arciconfraternità del Gonfalone" during their mission to Algiers from 1584 to 1589 focussed on physiognomic characteristics and, especially, on the topographical and social positioning of captives. The performative self-fashioning of the captive and the plausibility of his story placed him at the centre of the identificatory act and rendered it as a communicative process. The article analyses the fictions and frictions of communication between the southern and the northern shore of the Mediterranean and provides closer insight into the world of merchants who acted as brokers offering their services (especially financial) to families wishing to ransom a relative as well to institutionalized missions such as those of the "Gonfalone". The negotiations took place in a climate of uncertainty and distrust, where rumours were omnipresent and good information at the moment wanted was often lacking. The competitive actions of different political powers interfered in and temporarily blocked negotiations, creating the need for symbolic action to reinforce credibility in the absence of trust.