  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
