"A Course in Functional Analysis and Measure Theory" is a comprehensive textbook written by an experienced instructor. It offers an elegant and self-contained introduction to functional analysis, covering both fundamental and advanced topics. The content ranges from measure and integration theory to classical Banach and Hilbert spaces, as well as spectral theory for bounded operators. The book is structured to be suitable for both advanced undergraduate students and graduates. It includes over 1500 exercises of varying difficulty, which can be used for self-study as well as to accompany lectures. Historical and motivational notes complement the theoretical content and promote a deeper understanding of the subject.