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 original 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.