Both a theoretical physicist and mathematician, Ludwig Faddeev is best known for \"the Faddeev equations\", the first mathematically well-posed formulation of the quantum-mechanical three-body problem, which are foundational in few-body physics. Having made multiple seminal contributions to theoretical physics (Faddeev-Popov ghosts, Faddeev-Senjanovic quantization, Faddeev-Jackiw quantization among others), he was conferred numerous prizes and memberships of prestigious institutions in recognition of the importance of his work. These include the Dannie Heineman Prize, the Dirac Prize, the Max Planck Medal, the Shaw Prize and the Lomonosov Gold Medal among others.A gathering of contributions from some of the biggest names in physics and mathematics, this volume serves as a tribute to this legendary figure in mathematical physics. Volume contributors include: Fields medallist Sir Michael Atiyah, Jurg Froehlich, Roman Jackiw, Louis Nirenberg, Samson Shatashvili, Vladimir Korepin as well as Nobel laureates Frank Wilczek, C N Yang and Gerard \'t Hooft.