PDMS

Aveva Group Plc.
Supplier of software solutions and services to the process industries, including PDMS for plant design engineering, VANTAGE for engineering change management, and other datacentric design tools.
http://www.aveva.com/

Plantcon A/S
Danish PDMS sales, consulting, and training courses. Free PDMS macros. [Danish, English, and German]
http://www.plantcon.dk/

PlantWare's PDMS Information
Discussion of the benefits of using Cadcentre's PDMS (Plant Design Management System) software for collaborative 3D multi-user engineering.
http://www.pdms.dk/