This LNCS volume constitutes the proceedings of the International Joint Conference on Rough Sets, IJCRS 2026, held in Cádiz, Spain, during May 2026.The 27 full papers included in this book were carefully reviewed and selected from 106 submissions. These papers focus on following topical sections: Foundations and Models of Rough Sets; Computational Intelligence and Three-Way Decision.

This LNCS volume constitutes the proceedings of the International Joint Conference on Rough Sets, IJCRS 2026, held in Cádiz, Spain, during May 2026.The 27 full papers included in this book were carefully reviewed and selected from 106 submissions. These papers focus on following topical sections: Foundations and Models of Rough Sets; Computational Intelligence and Three-Way Decision.