- PAC - Planning Appeals Commission
- PCN - Personal Communications NetworK
- PPS - Planning Policy Statement
- PSRNI - A Planning Strategy for Rural Northern Ireland
- PSTN - Public Switched Telephone Network
- Permitted Development - Development which does not require planning permission such as certain agricultural and forestry developments.
- Planning Service - Section of the Department of the Environment responsible for planning.
- Pondage - See Flood Storage
- Prematurity - Making a planning decision before the relevant development plan has been completed or adopted.
- Proximity Principle - Highlights a need to treat and/or dispose of waste in reasonable proximity to the point at which it is generated.
- Putrescible - Liable to decompose or rot with an offensive smell.