Book excerpt: Well-researched reference on stable alternative electrocatalysts and electrode materials with the potential to transform chemistry and processes in sensor and energy related technologies Applied Polyoxometalate-Based Electrocatalysis delivers an overview of the variety of efficient applications of free POM and POM-based (nano)composites as exciting materials in the field of electrocatalysis. With a variety of sizes, shapes, composition, and physical and chemical properties, these composites have important properties, such as the ability to undergo reversible multivalence reductions/oxidations, leading to the formation of mixed-valence species, which brings about favorable electrocatalytic properties with regard to several electrochemical processes. Written by a highly qualified independent researcher internationally recognized for her contributions to materials for electrochemical energy-related reactions, Applied Polyoxometalate-Based Electrocatalysis includes information on: General methodologies used in the preparation of free POMs and POM-based nanocomposites and different strategies employed in electrode modification Role of POM-modified electrodes in oxidative and reductive electrocatalysis, including the detection/sensing of several (bio)molecules of interest and carbon dioxide electroreduction Application of POM-based (nano)composites, including the oxygen reduction reaction relevant to fuel cells, the oxygen and hydrogen evolution reactions, and batteries and supercapacitors Applied Polyoxometalate-Based Electrocatalysis is an essential reference on the subject for chemists, material scientists, chemical engineers, and institutions involved in work related to free POM and POM-based (nano)composites.