The port of Sumhuram was founded by the ruler of the kingdom of Hadramawt, more than 700 km from the capital, Shabwa, on the shore of the Indian Ocean, in nowadays Dhofar (Sultanate of Oman), a land famous for frankincense. This site has been under investigation by the Italian Mission to Oman (IMTO), under the direction of Alessandra Avanzini, for more than twenty years. The Report 4 volume presents the results of three different subjects of research, spanning from the presentation of the excavation of a residential complex, to the study of the very numerous bronze coins found in the city, to the analysis of the data available, allowing for the reconstruction of the history of the town in its chronological development from the 2nd century BC to the 5th century AD, through the study of ceramics and coins. Special attention is given to the very first period of occupation of the town, of which we had very few attestations until recently.