Pre-proceedings of the DECLARE 2019 Conference

This volume constitutes the pre-proceedings of the DECLARE 2019 conference, held on September 9 to 13, 2019 at the University of Technology Cottbus - Senftenberg (Germany). Declarative programming is an advanced paradigm for the modeling and solving of complex problems. This method has attracted increased attention over the last decades, e.g., in the domains of data and knowledge engineering, databases, artificial intelligence, natural language processing, modeling and processing combinatorial problems, and for establishing systems for the web. The conference DECLARE 2019 aims at cross-fertilizing exchange of ideas and experiences among researches and students from the different communities interested in the foundations, implementation techniques, novel applications, and combinations of high-level, declarative programming and related areas. The technical program of the event included invited talks, presentations of refereed papers, and system demonstrations. DECLARE 2019 consisted of the sub-events INAP, WFLP, and WLP: INAP - 22nd International Conference on Applications of Declarative Programming and Knowledge Management WFLP - 27th International Workshop on Functional and (Constraint) Logic Programming WLP - 33rd Workshop on (Constraint) Logic Programming