ACEM Conference on Road Ecology, Transportation Infrastructure, and Wildlife Conservation was held on 3 August 2021 via online Zoom conference. The conference’s welcoming address was presented by the ACEM member Ir. Patrick Augustin and the opening ceremony by the ACEM President, Ir. K. Sundraraj. The Speakers were Dr. Wong Ee Phin, Dr. G. Balamurugan, Nadine Brigitte Ruppert, Rob Ament, Tony Clevenger, Dr. Christine Fletcher, Benoit Goossens, Jo Leen Yap, Dr. Rodney van der Ree, and Isabelle Lackman. The conference attracted nearly sixty-seven participants.