This book constitutes the refereed post-conference proceedings of the 13^th International Conference on Ad Hoc Networks, ADHOCNETS 2021, held in December 2021, and the 16^th International Conference on Tools for Design, Implementation and Verification of Emerging Information Technologies, TRIDENTCOM 2021, held in November 2021. Both conferences were held virtually due to COVID 19 pandemic. The 15 full papers of ADHOCNETS 2021 were selected from 29 submissions and cover a variety of network paradigms including ad hoc networks (MANETs), wireless sensor networks (WSNs), vehicular ad hoc networks (Vanets), airborne networks, underwater networks, underground networks, personal area networks, and home networks, etc. It promises a wide range of applications in civilian, commercial, and military areas. The 18 full papers were selected from 47 submissions and deal the emerging technologies such as Industry 4.0, blockchain, deep learning, cloud/edge/fog computing, cyber physical systems, cybersecurity and computer communications.