The PRECIS-2 tool is an improved version of the original PRECIS tool, designed to help trialists make design decisions that align with the intended purpose of their trials. Developed with input from over 80 international trialists, clinicians, and policymakers, PRECIS-2 retains the simple wheel format of its predecessor but includes nine domains: eligibility criteria, recruitment, setting, organization, flexibility (delivery), flexibility (adherence), follow-up, primary outcome, and primary analysis. Each domain is scored on a 5-point scale (1=very explanatory to 5=very pragmatic) to facilitate discussion and consensus. The tool aims to support the explicit matching of design decisions to how the trial results are intended to be used, ensuring that trials are relevant and applicable to real-world settings. The paper provides guidance on how to use PRECIS-2, including four steps: identifying the trial's design approach, considering design choices for each domain, scoring these choices, and reviewing the overall design to ensure it aligns with the trial's purpose. The tool is intended for use by multidisciplinary teams during the trial design process to enhance the applicability and relevance of trial results.The PRECIS-2 tool is an improved version of the original PRECIS tool, designed to help trialists make design decisions that align with the intended purpose of their trials. Developed with input from over 80 international trialists, clinicians, and policymakers, PRECIS-2 retains the simple wheel format of its predecessor but includes nine domains: eligibility criteria, recruitment, setting, organization, flexibility (delivery), flexibility (adherence), follow-up, primary outcome, and primary analysis. Each domain is scored on a 5-point scale (1=very explanatory to 5=very pragmatic) to facilitate discussion and consensus. The tool aims to support the explicit matching of design decisions to how the trial results are intended to be used, ensuring that trials are relevant and applicable to real-world settings. The paper provides guidance on how to use PRECIS-2, including four steps: identifying the trial's design approach, considering design choices for each domain, scoring these choices, and reviewing the overall design to ensure it aligns with the trial's purpose. The tool is intended for use by multidisciplinary teams during the trial design process to enhance the applicability and relevance of trial results.