Invited Lectures -- Computational Power of Symport/Antiport: History, Advances, and Open Problems -- Structural Operational Semantics of P Systems -- Some Recent Results Concerning Deterministic P Systems -- Membrane Algorithms -- On Evolutionary Lineages of Membrane Systems -- Regular Presentations -- Number of Protons/Bi-stable Catalysts and Membranes in P Systems. Time-Freeness -- Symbol/Membrane Complexity of P Systems with Symport/Antiport Rules -- On P Systems as a Modelling Tool for Biological Systems -- Encoding-Decoding Transitional Systems for Classes of P Systems -- On the Computational Power of the Mate/Bud/Drip Brane Calculus: Interleaving vs. Maximal Parallelism -- A Membrane Computing System Mapped on an Asynchronous, Distributed Computational Environment -- P Systems with Memory -- Algebraic and Coalgebraic Aspects of Membrane Computing -- P Systems and the Modeling of Biochemical Oscillations -- P Systems, Petri Nets, and Program Machines -- On the Power of Dissolution in P Systems with Active Membranes -- A Linear Solution for QSAT with Membrane Creation -- On Symport/Antiport P Systems and Semilinear Sets -- Boolean Circuits and a DNA Algorithm in Membrane Computing -- Towards a Petri Net Semantics for Membrane Systems -- Quantum Sequential P Systems with Unit Rules and Energy Assigned to Membranes -- Editing Distances Between Membrane Structures -- Relational Membrane Systems -- On the Rule Complexity of Universal Tissue P Systems -- Non-cooperative P Systems with Priorities Characterize PsET0L.