The patient voice is critical to achieving value-based care, improving health outcomes, and advancing medical research. However, a key challenge is how to translate this “voice” into scientifically valid data that can inform evidence-based clinical decisions. One of the biggest barriers is the sheer variety of available patient-reported outcomes (PROs) and patient-reported outcome measures (PROMs) and the associated challenges of translation, validation, implementation, and interpretation, making it difficult to obtain valid and comparable health outcomes. The authors present a harmonized global approach to international standardization of PROs and PROMs. This approach has the potential to accelerate patient-centered care by facilitating the collection of accurate and comparable real-world evidence on health outcomes that matter most to patients. This proposed approach consists of two elements: a data collection process based on a common set of PROs and a state-of-the-art measurement approach based on item response theory. First, there is growing evidence that outcomes such as pain, fatigue, anxiety, depression, sleep disturbance, physical function, and the ability to participate in social roles and activities are relevant for most people, irrespective of their health condition. Measuring these outcomes routinely in all patients could increase outcome comparability and utility for a range of stakeholders. Second, a measurement strategy based on a state-of-the-art psychometric approach — using item response theory (IRT)-based item banks — offers short, flexible, sustainable, and universally applicable PROMs with robust measurement properties and a common measurement scale. The unique integration of these two elements offers the potential to collect comparable PROM data across patients and providers to support shared decision-making, which may lead to better outcomes. The Patient-Reported Outcomes Measurement Information System (PROMIS) is a globally used example of such an approach. The PROMIS Profile measures serve as a resource for measuring a harmonized core set of PROs across medical conditions, languages, and countries. To meet the United Nations Sustainable Development Goal of ensuring healthy lives and promoting well-being for all, at all ages, a collaborative effort is needed to achieve consensus on international standardization of PROs and PROMs to accelerate patient-centered care across health conditions, settings, and countries. The authors propose to routinely measure a core set of broadly relevant PROs in all patients, regardless of their health condition, with universally applicable IRT-based PROMs.