The major trend in modern logic is the move from logic to logics. The need for formal modelling of reasoning in various fields of science (philosophy, linguistics, AI, cognitive, social and management sciences) led to the design of hundreds of bespoke logics. For instance, the focus on multi-agent interaction and social behaviour has led to the introduction of logics specific to contexts involving e.g. dynamic changes, uncertainty, incomplete and inconsistent information, which are at odds with reasoning as is formalized in classical logic. This rapid expansion has generated the need to develop overarching theories capable to provide uniform proofs of fundamental properties--such as soundness, completeness, analiticity, decidability--for each member of vast families of logics, while at the same time accounting in a modular way for the specific features of each. Algebraic proof theory is a research area in which these general results can be achieved using insights from algebraic logic, universal algebra, duality and representation theory for classes of algebras. This workshop aims at bring together researchers in algebraic proof theory and its applications, explore promising research directions, and foster collaborations.