The new EC Charges Directive coming into force on 15 March 2011 stipulates, among other principles, the need for "regular consultation" (as per article 6) on airport charges and quality of service.
CIP Engagement Best Practices
IATA's CIP Engagement best practices clarify what IATA’s member airlines require in terms of "regular consultation". The document is based on the experience gained in the consultation process currently underway between Amsterdam Airport Schiphol and KLM.
These documents outline IATA's recommendations to ensure meaningful engagement.