The Rules of Korfball are defined by the International Korfball Federation and must be followed by all IKF members. However, countries may be interested in making experiments with the rules of the game, either by experimenting with changes to existing rules or by experimenting with new rules. The IKF encourages IKF members to do so in light of game development.
Following the IKF Playing Rules Experiments Procedure, the IKF informs the IKF members about this possibility every year, after which the National Federations can request an experiment at least 6 weeks before the start of the proposed experiment.
For more information, see Playing Rules Experiments Procedure 2021.