The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. Despite significant endorsement by funders and journals, adherence to these guidelines has been inconsistent, and improvements in reporting quality have not been achieved. To address this, the authors introduce ARRIVE 2.0, which has been updated and reorganized to facilitate practical use. The guidelines are divided into two sets: the "ARRIVE Essential 10," which constitutes the minimum requirement, and the "Recommended Set," which describes the research context. This division supports a stepwise approach to implementation, helping journal editors and reviewers verify that critical information is reported. The accompanying Explanation and Elaboration document provides context and rationale for each item, clarifying key concepts and providing illustrative examples. The revised guidelines aim to enhance the rigor and transparency of animal research, ensuring that researchers, reviewers, and journal editors are better equipped to improve the reproducibility of scientific findings.The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments) were originally developed in 2010 to improve the reporting of animal research. Despite significant endorsement by funders and journals, adherence to these guidelines has been inconsistent, and improvements in reporting quality have not been achieved. To address this, the authors introduce ARRIVE 2.0, which has been updated and reorganized to facilitate practical use. The guidelines are divided into two sets: the "ARRIVE Essential 10," which constitutes the minimum requirement, and the "Recommended Set," which describes the research context. This division supports a stepwise approach to implementation, helping journal editors and reviewers verify that critical information is reported. The accompanying Explanation and Elaboration document provides context and rationale for each item, clarifying key concepts and providing illustrative examples. The revised guidelines aim to enhance the rigor and transparency of animal research, ensuring that researchers, reviewers, and journal editors are better equipped to improve the reproducibility of scientific findings.