** Apologies for multiple postings ** 33rd International Symposium on Logic-based Program Synthesis and Transformation (LOPSTR 2023) Co-located with PPDP 2023 as part of SPLASH 2023 October 23-24, 2023 - Cascais, Lisbon, Portugal https://lopstr.github.io/2023/ Important dates:  - Abstract submission: May 19, 2023 (AoE)  - Paper submission: May 26, 2023 (AoE)  - Author notification: July 24, 2023 (AoE)  - Camera-ready: August 18, 2023  - Symposium: October 23-24, 2023 OVERVIEW The aim of the LOPSTR series is to stimulate and promote international research and collaboration on logic-based program development. LOPSTR is open to contributions in logic-based program development in any language paradigm. LOPSTR has a reputation for being a lively, friendly forum for presenting and discussing work in progress. LOPSTR 2023 will be held in-person at Hotel Cascais Miragem in Cascais, Lisbon, Portugal and will be co-located with PPDP 2023 as part of SPLASH 2023. At least one of the authors of the accepted paper is expected to attend the conference and present the paper. Information about venue and travel is available on the SPLASH 2023 website. Topics of interest cover all aspects of logic-based program development, all stages of the software life cycle, and issues of both programming-in-the-small and programming-in-the-large, including, but not limited to:  - synthesis  - transformation  - specialization  - inversion  - composition  - optimisation  - specification  - analysis and verification  - testing and certification  - program and model manipulation  - AI-methods for program development  - verification and testing of AI-based systems  - transformational techniques in software engineering  - logic-based methods for security, cyber-physical and distributed    system  - applications, tools and industrial practice Survey papers that present some aspects of the above topics from a new perspective and papers that describe experience with industrial applications and case studies are also welcome. PAPER SUBMISSION Submissions can be made in two categories:  - Regular Papers (15 pages max.)  - Short Papers (8 pages max.) References do NOT count towards the page limit. Additional pages may be used for appendices not intended for publication. Reviewers are not required to read the appendices, and thus papers should be intelligible without them. All submissions must be written in English. Submissions must not substantially overlap with papers/tools that have been published or that are simultaneously submitted to a journal, conference, or workshop with refereed proceedings. Submissions of Regular Papers must describe the original work. Work that already appeared in unpublished or informally published workshop proceedings may be submitted (please contact the PC chair in case of questions). Submissions of Short Papers may include presentations of exciting if not fully polished research and tool demonstrations that are of academic and industrial interest. Tool demonstrations should describe the relevant system, usability, and implementation aspects of a tool. All accepted papers will be included in the conference proceedings and published by Springer as a Lecture Notes in Computer Science (LNCS) volume. After the symposium, a selection of a few best papers will be invited for submission to rapid publication in the Journal of Theory and Practice of Logic Programming (TPLP). Authors of selected papers will be invited to revise and/or extend their submissions to be considered for publication. The papers submitted to TPLP will be subject to the standard reviewing process of the journal. SUBMISSION GUIDELINES Authors should submit an electronic copy of the paper (written in English) in PDF, formatted in the Lecture Notes in Computer Science style. Each submission must include on its first page the paper title; authors and their affiliations; contact author's email; abstract; and three to four keywords which will be used to assist the PC in selecting appropriate reviewers for the paper. Authors should consult Springer's authors' instructions at the author's page, and use their proceedings templates, either for LaTeX (available also in overleaf) or for Word, for the preparation of their papers. Springer encourages authors to include their ORCIDs in their papers. In addition, upon acceptance, the corresponding author of each paper, acting on behalf of all of the authors of that paper, must complete and sign a Consent-to-Publish form. The corresponding author signing the copyright form should match the corresponding author marked on the paper. Once the files have been sent to Springer, changes relating to the authorship of the papers cannot be made. Page numbers (and, if possible, line numbers) should appear on the manuscript to help the reviewers in writing their report. So, for LaTeX, we recommend that authors use: \pagestyle{plain} \usepackage{lineno} \linenumbers Papers should be submitted via EasyChair: https://easychair.org/conferences/?conf=lopstr2023 BEST PAPER AWARD Thanks to Springer's sponsorship, two best paper awards (one for each submission category), with a 500 EUR prize, will be given at LOPSTR 2023. The program committee will select the winning papers based on relevance, originality and technical quality but may also take authorship into account (e.g. a student paper). PROGRAM CHAIRS Robert Glück, University of Copenhagen, Denmark Bishoksan Kafle, IMDEA Software Institute, Spain PUBLICITY CHAIR Daniel Jurjo Rivas, IMDEA Software Institute, Spain PROGRAM COMMITTEE MEMBERS Slim Abdennadher, German International University, Egypt José Júlio Alferes, Universidade Nova de Lisboa, Portugal Roberto Amadini, University of Bologna, Italy William Byrd, University of Alabama at Birmingham, USA Michael Codish, Ben-Gurion University of the Negev, Israel Gregory Duck, National University of Singapore, Singapore Isabel García-Contreras, University of Waterloo, Canada Ashutosh Gupta, IIT Bombay, India Gopal Gupta, The University of Texas at Dallas, USA Michael Hanus, University of Kiel, Germany Temesghen Kahsai, Amazon, USA Maja Hanne Kirkeby, Roskilde University, Denmark Michael Leuschel, Heinrich Heine University Düsseldorf, Germany Nai-Wei Lin, National Chung Cheng University, Taiwan Fred Mesnard, University of Reunion, France José F. Morales, IMDEA Software Institute, Spain Carlos Olarte, Universitè Sorbonne Paris Nord, France Alberto Pettorossi, Università di Roma Tor Vergata, Italy Christoph Reichenbach, Lund University, Sweden Peter Schachte, The University of Melbourne, Australia Helge Spieker, Simula Research Laboratory, Norway Theresa Swift, Universidade Nova de Lisboa, Portugal Laura Titolo, National Institute of Aerospace, USA Kazunori Ueda, Waseda University, Japan Germán Vidal, Universitat Politècnica de València, Spain Nisansala Yatapanage, Australian National University, Australia Florian Zuleger, Vienna University of Technology, Austria HISTORY LOPSTR is a renowned symposium that has been held for more than 30 years.  The first meeting was held in Manchester, UK in 1991. Information about previous symposia: http://lopstr.webs.upv.es/. You might have a look at the contents of past LOPSTR symposia at DBLP (https://dblp.uni-trier.de/db/conf/lopstr/index.html) and past LNCS proceedings at Springer (https://link.springer.com/conference/lopstr).