The album amicorum quickly establishes itself in the 16th century as an independent means of expression and communication, extending beyond the close circle of reformers and scholars around the University of Wittenberg. Through the example of three friendship albums, aspects of the practical handling of an album amicorum are demonstrated through entries and owners (approximately 1550 to 1650). The initiators of the albums from the East Prussian-Baltic cultural area maintain contacts with the Prague court of Rudolf II. In the literary-historical context of the time, the friendship album can be distinguished from other life testimonies. Nevertheless, the album amicorum, as an ego-document, forms part of this early modern book culture. A sketch of this relationship concludes the study, taking into account both the handwritten collection of sayings by the humanists and the friendship album as an object of book collectors and institutions of the early modern period.