The abbreviation DPD may stand for: Computing Dead Peer Detection, an IPSec VPN feature Delegated Path Discovery, a public-key query method Densely packed decimal, a system of binary encoding for decimal digits Engineering and technology Diffusion pressure deficit Digital Pre-Distortion, a subset of Multidimensional Digital Pre-distortion that deals with linearization of non-orthogonal, non-linear systems. Digital product definition, a near-synonym of model-based definition Dissipative particle dynamics, a mesoscopic particle-based materials simulation technique Diver propulsion device, an underwater vehicle Law EU Dangerous Preparations Directive EU Data Protection Directive Development Plan Document, in town and country planning in England and Wales Digital Phonorecord Delivery, a U.S. Copyright Office process for sound recording registration Mental disorders Dependent personality disorder, over-dependence on others Depersonalization-derealization disorder, feeling detached from one's self Depressive personality disorder, disorder with depressive features Organic chemicals Dihydropyrimidine dehydrogenase, an enzyme N,N-diethyl-p-phenylenediamine, a phenylenediamine often used to determine chlorine in water Police in the United States Denver Police Department, Colorado Detroit Police Department, Michigan Dallas Police Department, Texas Politics Democratic Party of Germany (Demokratische Partei Deutschlands or "DPD"), liberal party in Germany Regional Representative Council (), a chamber of the Indonesian parliament Other uses DPDgroup, an international parcel-delivery business Diccionario panhispánico de dudas (Pan-Hispanic Dictionary of Doubts), Spanish lexicon Distributed participatory design Dorking Deepdene railway station, England (GBR code: DPD)