The CIFOR Guidelines for Foodborne Illness Complaint Systems were developed to address a gap in the Second Edition of the CIFOR Guidelines for Foodborne Disease Outbreak Response regarding the use of foodborne illness complaint systems to detect foodborne disease outbreaks, and are intended to be included for review and incorporation in the Third Edition of the CIFOR Guidelines for Foodborne Disease Outbreak Response. Who should use it: Any public health entity involved in consumer complaint-based surveillance, response, and investigation. The final draft for review and incorporation into the Third Edition of the CIFOR Guidelines for Foodborne Disease Outbreak Response includes the following sections: A comprehensive review of current foodborne illness complaint systems, Generalized CIFOR Guidelines for Implementing Foodborne Illness Complaint Systems, Guidelines adapted for multiple agency structures, A template for incorporation into third edition of the CIFOR Guidelines, Appendix 1. Foodborne Illness Complaint Form developed by EHSNET, Appendix 2: The One-Pager of Key Elements of Complaint System Operational Guidelines, Appendix 3. Complaint systems work group members, participants and reviewers