The two volume set LNCS 14958 + 14959 constitutes the proceedings of the 15th International Conference of the CLEF Association, CLEF 2024, held in Grenoble, France, during September 9–12, 2024.The proceedings contain 11 conference papers;

Lab Overviews.- Overview of BioASQ 2024 The twelfth BioASQ challenge on Large-Scale Biomedical Semantic Indexing and Question Answering.- Overview of the CLEF2024 CheckThat Lab Check Worthiness, Subjectivity, Persuasion, Roles, Authorities and Adversarial Robustness.- Overview of ELOQUENT 2024 shared tasks for evaluating generative language model quality.- Overview of eRisk 2024 Early Risk Prediction on the Internet.- Overview of EXIST 2024 Learning with Disagreement for Sexism Identification and Characterization in Tweets and Memes.- Intelligent Disease Progression Prediction Overview of iDPP CLEF 2024.- Overview of the ImageCLEF 2024 Multimedia retrieval in medical applications.- Overview of JOKER CLEF 2024 Automatic Humour Analysis.- Overview of LifeCLEF 2024 Challenges on Species Distribution Prediction and Identification.- Overview of the CLEF 2024 LongEval Lab on Longitudinal Evaluation of Model Performance.- Overview of PAN 2024 Multi Author Writing Style Analysis, Multilingual Text Detoxification, Oppositional Thinking Analysis, and Generative AI Authorship Verification.- Overview of QuantumCLEF 2024 The Quantum Computing Challenge for Information Retrieval and Recommender Systems at CLEF.- Overview of the CLEF 2024 SimpleText Track Improving Access to Scientific Texts for Everyone.- Overview of Touche 2024 Argumentation Systems.