BACKGROUND: There exists scant evidence on the optimal approaches to integrating patient-reported outcomes (PROs) in clinical practice. This study gathered oncology practitioners' experiences with implementing PROs in cancer care. METHODS: Between December 2019 and June 2020, we surveyed practitioners who reported spending > 5% of their time providing clinical care to cancer patients. Respondents completed an online survey describing their experiences with and barriers to using PROs in clinical settings. RESULTS: In total, 362 practitioners (physicians 38.7%, nurses 46.7%, allied health professionals 14.6%) completed the survey, representing 41 countries (Asia-Pacific 42.5%, North America 30.1%, Europe 24.0%, others 3.3%). One quarter (25.4%) identified themselves as "high frequency users" who conducted PRO assessments on > 80% of their patients. Practitioners commonly used PROs to facilitate communication (60.2%) and monitor treatment responses (52.6%). The most commonly reported implementation barriers were a lack of technological support (70.4%) and absence of a robust workflow to integrate PROs in clinical care (61.5%). Compared to practitioners from high-income countries, more practitioners in low-middle income countries reported not having access to a local PRO expert (P < .0001) and difficulty in identifying the appropriate PRO domains (P = .006). Compared with nurses and allied health professionals, physicians were more likely to perceive disruptions in clinical care during PRO collection (P = .001) as an implementation barrier. CONCLUSIONS: Only a quarter of the surveyed practitioners reported capturing PROs in routine clinical practice. The implementation barriers to PRO use varied across respondents in different professions and levels of socioeconomic resources. Our findings can be applied to guide planning and implementation of PRO collection in cancer care.