PTD

PTD may refer to:

Law

 * Permanent total disability, in insurance law
 * Pre-trial diversion, in criminal justice
 * Protected trust deed, in Scottish bankruptcy law

Science, technology and mathematics

 * Pathfinder Technology Demonstrator, ongoing NASA missions to test miniaturized satellites
 * Peak–trough difference, of an oscillating curve
 * Poloidal–toroidal decomposition, in vector calculus
 * Pre-term delivery, a human birth under 37 weeks gestation
 * PTD-DBM, a synthetic peptide to reverse hair loss
 * Pre-Thread Data file, in Microsoft's .NET Framework

Other uses

 * Participatory technology development, in international agriculture programs
 * Partido de los Trabajadores Dominicanos or the Dominican Workers' Party
 * Potsdam Municipal Airport, New York, US (FAA LID: )
 * Post travel depression, a mood disorder
 * Prevention through design, in occupational health and safety