This three-volume set, LNCS 17126-17128, constitutes the refereed proceedings of the 25th International Semantic Web Conference, ISWC 2026, held in Bari, Italy, during October 25–29.

The 96 full papers and 4 keynotes included in these proceedings were carefully reviewed and organised in different conference tracks: 51 full papers were accepted for the Research Track out of 232 submissions, and 27 full papers for the Resources Track out of 90 submissions. The remaining full papers included in these proceedings are from the In-Use Track (12 papers out of 29 submissions) and the Visionary Ideas Track (6 papers out of 22 submissions). The volumes are structured as follows:

Part I: Rearch Track 

Part II: Research Track and Resources Track

Part III: Resources Track, In-Use track and Visionary Ideas