The citizen participation process "The Planning Cell" was developed in the 1970s by Prof Dr Dienel at the University of Wuppertal. Following on from this tradition, the IDPF has adapted and further developed it to meet today's standards and needs. The duration of a planning cell is at least 3 days and is organised with at least 25 participants. There is always one female and one male moderator.

The core components of the planning cell are

1. Aleatory invitation procedure
2. Randomised group assignments
3. Lecture-based topic processing
4. Plenary and group work phases
5. Group-based recommendations
6. Individual votes
7. Politician / expert hearing
8. Evaluations of the socio-demographics
9. Preparation of a citizens' report

Further developments are

1. Kick-off events for all interested citizens
2. Internet presence as an information platform
3. Interlinked online participation
4. Video recordings of the speakers
5. Stakeholder process in the run-up to public participation
6. Closing event with presentation of the results
7. Digital voting process in the planning cell
8. Evaluation of the entire public participation process
9. Citizen surveys before or after the planning cell
10. Press and public relations work relating to the participation process

Not all further developments are implemented in every planning cell. It depends on the subject area, the time of participation and the level of escalation or the media importance of the topic.