Keryx, founded in 2011 in Graz as a new «Zeitschrift für Antike», is devoted to the latest studies and congress proceedings on antiquity, open to and combining the themes and methodological frames of archaeology, historiography, epigraphy, and philology. This 7th volume of Keryx, reporting the results of panel 5.14 of the XIXth International Congress of Classical Archaeology on «Trade and Commerce in the Harbour Town of Ostia» gives a best-practice example of how deep insights into life and commerce in antiquity may be won by the fruitful composition of the different research fields. I would like to express my deep gratitude to Alice Landskron and Claudia Tempesta for organising the workshop in Bonn in 2018 and carefully editing this volume. From the five contributions we are therefore able to learn about fascinating economic structures and ways of expressing individual identity, not only in Ostia, functioning as a focal point and micro-cosmos for urban sociology and development, but also about the network of cities and provinces in the Roman Empire at a large scale. This shows once more that not only theory-driven-research, but profound case studies with careful analyses can function as a proper instrument for generalised conclusions in our joint efforts of understanding antiquity. – Peter Scherrer