This book constitutes the refereed proceedings of the 15th International Workshop on Communication Technologies for Vehicles, Nets4Cars/Nets4Trains/Nets4Aircraft 2020, held in Bordeaux, France, in November 2020.

The 18 full papers were carefully reviewed and selected from 22 submissions. The selected papers present orig-inal research results in areas related to the physical layer, communication protocols and standards, mobility and traffic models, experimental and field operational testing, and performance analysis.