In Progress Information Service (PID) is a paradigm of supporting users in their work by delivering them information related to the current working situation. Unlike information search process where the user has to initiate the search, PID tries to identify the user’s current information need.
Applications of PID
PID can be used for just-in-time learning embedded in working processes.
Examples of systems providing PID features
Intellext Watson was a prominent tool illustrating the concept of lightweight PID.
Classification of PID methods
Classification of PID tools is given in 
- Jump up^Holz, Harald; Maus, Heiko; Bernardi, Ansgar; Rostanin, Oleg (2005). “From Lightweight, Proactive Information to Business Process-Oriented Knowledge Management”. Journal of Universal Knowledge Management . 0 (2): 101-127. CiteSeerX 10.1.1.63.8027 .