• Submission deadline: June 13, 2021 UTC-12
  • Notification: July 12, 2021


Workshop on the International Planning Competition

    The International Planning Competition (IPC) is held every few years in the context of ICAPS. It empirically evaluates state-of-the-art planning systems on a number of benchmark problems. The goals of the IPC are to promote planning research, highlight challenges in the planning community and provide new and interesting problems as benchmarks for future research. The IPC has an important role in the ICAPS community, being a forum to compare different algorithmic ideas and implementations, and setting standards for research and evaluation in the area.

    Similar to the lineage of IPC workshops organised at ICAPS 2003, 2007, 2012, 2015, and 2019 this workshop aims to review the current status of the IPC, analyse the results of the last IPC (2020), and provide a venue for discussing aspects that will be helpful for preparing forthcoming competitions.


    Topics include, but need not be limited to:

    • Past, present and future of the IPC
    • Tracks: Proposing new and/or revising the current tracks
    • Domain Definition Languages: benefits and limitations. Should larger subsets of PDDL/RDDL/HDDL be considered in next editions of the IPC? Should the input languages evolve in some way?
    • Benchmark Domains: Discussion/Analysis of existing domains. Are IPC benchmarks a good standard for evaluation of planners? How should instances be chosen for the competition? Should there be randomly generated instances?
    • Evaluation Metrics: Should we adapt the metrics used for evaluating the performance of planners? How should the winners of the competition be decided (e.g. analysis of advantages and disadvantages of IPC 2018 & 2020 vs. SPARKLE Planning challenge 2019)?
    • Results: interpretation of past results, new ideas about how to analyze/compare the performance of planners beyond the score of the competition.
    • Rules: Should portfolios be given a special treatment? Should there be any limits on re-using code from others?
    • Tools: Can we automate large parts of the IPC to make organising an IPC track easier?


    We encourage submissions in three formats. All submissions should be accompanied by a paper in AAAI style (the author kit is available at https://www.aaai.org/Publications/Templates/AuthorKit21.zip ). In all tracks you can choose the length of your submission freely between 1-8 pages + one page for references. Please choose a length appropriate for the format of your submission.

    • long presentations have a 30 minute slot, including discussions. We expect most papers for this format will make use of all 8 pages.
    • short presentations have a 15 minute slot, including discussions. We expect the average paper in this format will have around 4 pages.
    • super-short presentations have a 5 minute slot, including discussion. We expect submissions to consist of an idea that can be presented on 1-2 slides but lead to some discussion, like a suggestion for a new track or metric. Submissions in this track should consist of a title and abstract, so no PDF submission is required (though it is also welcomed).

    As suggested by the list of topics, we encourage the submission of position papers as well as other submissions that do not fit the mold of a typical conference paper.

    The review process will be double blind. Submissions must be made via easychair (https://easychair.org/conferences/?conf=wipc2021)

    Deadlines and Dates

    • Paper Submission: June 13
    • Notification of acceptance/rejection: July 12
    • Camera-ready paper submissions: August 1
    • HPlan Workshop: Wednesday, 4 August, 2021 (2 hours), see ICAPS schedule (day 3) for time zone selection! Some selected time zones:
      • 3 am to 5 am in parts of USA (EST)
      • 4 am to 6 am in e.g., Brasilia, Brazil (BRT)
      • 7 am to 9 am at virtual ICAPS (GMT)
      • 9 am to 11 am in e.g., Germany (MEST)
      • 5 pm to 7 pm in e.g., Canberra, Sydney, Melbourne (AEST)

    Accepted papers

    • Online Policy Improvement for Probabilistic Planning: Benchmarks and Baselines
      by Murugeswari Issakkimuthu and Alan Fern
    • Designing an Adaptable Benchmark and Competition Simulation for Integrated Planning and Execution
      by Liudvikas Nemiro, Gerard Canal, Oscar Lima, Michael Cashmore, and Mak Roberts


    The workshop proceedings are available


    7:00-9:00 GMT, Plenum Session:
    • 7:00-7:15: Recap of IPC 2020 on Hierarchical Planning
    • 7:15-7:30: IPC 2020 Planner Presentation: HyperTensioN (slides)
    • 7:30-7:45: IPC 2020 Planner Presentation: Lilotane (slides)
    • 7:45-8:00: IPC 2020 Planner Presentation: pyHiPOP (slides)
    • 8:00-8:25: Online Policy Improvement for Probabilistic Planning: Benchmarks and Baselines (slides)
    • 8:25-8:45: Designing an Adaptable Benchmark and Competition Simulation for Integrated Planning and Execution(slides)
    • 8:45-9:00: An ELO System for Skat and other Games of Chance(slides)


    • Gregor Behnke (University of Freiburg)
    • Daniel Höller (Saarland University)
    • Pascal Bercher (The Australian National University)