Sixth International Workshop on Structures and Deduction 2026

SD'26 is the sixth in a series of workshops aiming to gather various communities of structural proof theorists. The main interest is in new algebraic and geometric results in proof theory which expand our abilities to manipulate proofs, help to reduce bureaucracy in deductive systems, and ultimately lead to new methods for proof search and new kinds of proof certificates.

There have been five previous editions of Structures and Deduction:

• the ICALP 2005 workshop SD05 in Lisbon,
• the ESSLLI 2009 workshop SD09 in Bordeaux,
• the CSL-LICS 2014 workshop SD14 in Vienna,
• the FSCD 2017 workshop SD17 in Oxford,
• the FSCD 2019 workshop SD19 in Dortmund,

Themes of the workshop include but are not limited to:

• Syntactic representations of proofs, such as sequent calculi and deep inference systems, in their focussed and unfocussed variants.
• Combinatorial representations of proofs, such as proof nets, flow graphs and expansion trees.
• Algebraic representations of proofs, for example via game semantics or category theory.
• Methods for proof manipulation and normal forms of proofs, such as cut-elimination, rule permutations and proof compression.
• Formulas-as-types interpretations of proofs, such as Curry-Howard correspondences and witness extraction.
• Methods for incorporating computation and rewriting in proof search, such as deduction modulo or cyclic proofs.
• Complexity theoretic aspects of proof representations, such as decision procedures from proof search, proof complexity and normalisation complexity.

As well as theoretical work in the form of regular papers, we encourage submission of implementations, tools and system descriptions.

Contributions can be regular papers, but also work in progress, programmatic/position papers or tutorials. Submissions should be formatted with the LNCS LaTeX style, and should take between two and fifteen pages, to allow the committee to assess their merits with reasonable effort. This limit can be relaxed for the versions that will be presented at the workshop, depending on the total bulk of the accepted contributions.

• Deadline for submissions: April 23, 2026
• Notification of acceptance: May 23, 2026
• Deadline for final versions: TBA
• Workshop dates: July 24 - 25, 2026

TBA

Victoria Barrett (Inria and LIX, Palaiseau)
Lutz Straßburger (Inria and LIX, Palaiseau)