This book provides a selection of reports and survey articles on the latest research in the area of single and multivariable operator theory and related fields. The latter include singular integral equations, ordinary and partial differential equations, complex analysis, numerical linear algebra, and real algebraic geometry ¿ all of which were among the topics presented at the 26th International Workshop in Operator Theory and its Applications, held in Tbilisi, Georgia, in the summer of 2015.
Moreover, the volume includes three special commemorative articles. One of them is dedicated to the memory of Leiba Rodman, another to Murray Marshall, and a third to Boris Khvedelidze, an outstanding Georgian mathematician and one of the founding fathers of the theory of singular integral equations.
The book will be of interest to a broad range of mathematicians, from graduate students to researchers, whose primary interests lie in operator theory, complex analysis and applications, as well as specialists in mathematical physics.

Remembering Leiba Rodman 1949-2015, at IWOTA 2015.- A Brief Mathematical Obituary.- Interpolation and Transfer-function Realization for the Noncommutative Schur-Agler Class.- Lattice Theory and Toeplitz Determinants.- All Solutions to an Operator Nevanlinna-Pick Interpolation Problem.- Projective Quantum Modules and Projective Ideals of C¿-algebras.- On the Determinacy of the Moment Problem for Symmetric Algebras of a Locally Convex Space.- On the Partial Indices of Triangular Matrix Functions with Prescribed Indices of Their Diagonal Entries.- Toeplitz Operators via Sesquilinear Forms.