This special issue of the IEEE Journal on Selected Areas in Information Theory is dedicated to the memory of Alexander Vardy, a pioneer in the theory and practice of channel coding. His ground-breaking contributions ranged from unexpected solutions of long-standing theoretical conjectures to ingenious decoding algorithms that broke seemingly insurmountable barriers to code performance. Inspired not just by the mathematical beauty of coding theory but also by its engineering utility, Alex developed novel coding techniques that have had a profound impact on modern information technology. At the same time, his innovations have left their imprint on other scientific disciplines, such as information theory, computer science, and discrete mathematics.