V.G. Maz'ya is author or co-author of more than 300 scientific works on various fields of functional analysis, function theory, numerical analysis, partial differential equations and their application. This collection of articles in two volumes is dedicated to him on the occasion of his 60th birthday. The first volume contains surveys that show his enormous productivity and the large variety of his work. The second volume consists of artivles by outstanding experts on various problems in functional analysis, potential theory, linear and nonlinear partial differential equations, theory of function spaces and numerical analysis.