This volume contains the papers presented at CP 2009: The 15th International Conference on Principles and Practice of Constraint Programming. It was held from September 20–24, 2009 at the Rectory of the New University of Lisbon, Portugal. Everyone involved with the conference thanks our sponsors for their support. There were 128 submissions to the research track, of which 53 were accepted for a rate of 41.4%. Each submission was reviewed by three reviewers, with a small number of additional reviews obtained in exceptional cases. Each review waseitherbyaProgrammeCommitteemember,orbyacolleagueinvitedtohelp by a committee member thanks to their particular expertise. Papers submitted as long papers were accepted at full length or not at all. It is important to note that papers submitted as short papers were held to the same high standards of qualityas long papers. There is thus no distinction in these proceedings between long and short papers, except of course the number of pages they occupy. As it happens, the acceptancerates of short and long papers wereverysimilar indeed. Therewere13submissionstotheapplicationtrack,ofwhich8wereaccepted, fora rateof61.5%.Papersunderwentthe samereviewprocessasregularpapers, and there was not a separate committee for reviewing application track papers. However, papers in the application track were not required to be original or novel research, but to be original and novel as an application of constraints.

This book constitutes the refereed proceedings of the 15th International Conference on Principles and Practice of Constraint Programming, CP 2009, held in Lisbon, Portugal in September 2009. The 61 revised full papers presented together with the abstracts of three invited talks were carefully reviewed and selected from 141 submissions. All current issues of computing with constraints are addressed, ranging from methodological and foundational aspects - using algorithms, environments, languages, models and systems - to solving real-world problems in various application fields.

This book constitutes the proceedings of the 25th International Conference on Principles and Practice of Constraint Programming, CP 2019, held in Stamford, CT, USA, France, in September/October 2019. The 44 full papers presented in this volume were carefully reviewed and selected from 118 submissions. They deal with all aspects of computing with constraints including theory, algorithms, environments, languages, models, systems, and applications such as decision making, resource allocation, scheduling, configuration, and planning. The papers were organized according to the following topics/tracks: technical track; application track; multi-agent and parallel CP track; testing and verification track; CP and data science track; computational sustainability; and CP and life sciences track.

The 16th annual International Conference on the Principles and Practice of Constraint Programming (CP 2010) was held in St. Andrews, Scotland, during September 6–10, 2010. We would like to thank our sponsors for their generous support of this event. This conference is concerned with all aspects of computing with constraints, including:theory,algorithms,applications,environments,languages,modelsand systems. We received a wide variety of submissions, each of which was reviewed by at least three referees. Referees were chosen for each submission by an initial bidding process where Program Committee members chose papers from their area of interest. The range of expertise represented by the large Program C- mittee meant that almost all submissions were reviewed by subject experts on the Program Committee, or by colleagues chosen by members of the Program Committee for their particular expertise. Papers weresolicitedeither as long (15 page), or short (8 page) submissions. Short-paper submissions were refereed to exactly the same high standards as long-paper submissions but naturally were expected to contain a smaller quantity of new material. Thus there is no disti- tion in these proceedings between short and long papers. I used the excellent EasyChair conference management system to support this process of reviewing, and for the collation and organization of these proceedings. Submissions were made either to the applications track or to the research track. Therewere101(23short)researchtracksubmissionsofwhich36(8short) wereaccepted,whichisa36%(35%ofshort)acceptancerate. Applicationstrack submissions received special consideration and the acceptance rate was sign- cantly higher than for the research track.

This book constitutes the refereed proceedings of the 8th International Conference on Principles and Practice of Constraint Programming, CP 2002, held in Ithaca, NY, USA in September 2002. The 38 revised full papers and 6 innovative application papers as well as the 14 short papers presented toghether with 25 abstracts from contributions to the doctoral program were carefully reviewed and selected from 146 submissions. All current issues in constraint processing are addressed, ranging from theoretical and foundational issues to application in various fields.

This book constitutes the refereed conference proceedings of the 20th International Conference on Principles and Practice of Constraint Programming, CP 2014, held in Lyon, France, in September 2014. The 65 revised papers presented together with 4 invited talks were carefully selected from 108 submissions. The scope of CP 2014 includes all aspects of computing with constraints, including theory, algorithms, environments, languages, models, systems, and applications such as decision making, resource allocation, and agreement technologies.

This book constitutes the refereed proceedings of the 12th International Conference on Principles and Practice of Constraint Programming, CP 2006, held in Nantes, France in September 2006. The 42 revised full papers and 21 revised short papers presented together with extended abstracts of four invited talks were carefully reviewed and selected from 142 submissions. All current issues of computing with constraints are addressed.