Roughly every two years, the ICAPS conference hosts the International Planning Competition (IPC), in which the participating planning systems compete against each other on a set of planning benchmarks unknown to the participants. In the years in between other competitions related to planning are sometimes carried out, they cover -- to provide just two examples -- proving unsolvability or concern modelling assistance.
The planning competitions cover different problem classes (like classical planning, planning under uncertainty, or planning with time). In 2020, the IPC covered one track only, which was on Hierarchical Task Network (HTN) planning. This was the first time HTN planning systems competed in an IPC.
The IPC 2020 was organized by Gregor Behnke, Daniel Höller, and Pascal Bercher. For results, competing planning systems (source code and executables), and more -- visit its website: ipc.hierarchical-task.net