Purpose Informed self-assessment describes the set of processes through which individuals use external and internal data to generate an appraisal of their own abilities. The purpose of this project was to explore the tensions described by learners and professionals when informing their self-assessments of clinical performance. Method This 2008 qualitative study was guided by principles of grounded theory. Eight programs in five countries across undergraduate, postgraduate, and continuing medical education were purposively sampled. Seventeen focus groups were held (134 participants). Detailed analyses were conducted iteratively to understand themes and relationships. Results Participants experienced multiple tensions in informed self-assessment. Three categories of tensions emerged: within people (e. g., wanting feedback, yet fearing disconfirming feedback), between people (e. g., providing genuine feedback yet wanting to preserve relationships), and in the learning/practice environment (e. g., engaging in authentic self-assessment activities versus "playing the evaluation game"). Tensions were ongoing, contextual, and dynamic; they prevailed across participant groups, infusing all components of informed self-assessment. They also were present in varied contexts and at all levels of learners and practicing physicians. Conclusions Multiple tensions, requiring ongoing negotiation and renegotiation, are inherent in informed self-assessment. Tensions are both intraindividual and interindividual and they are culturally situated, reflecting both professional and institutional influences. Social learning theories (social cognitive theory) and sociocultural theories of learning (situated learning and communities of practice) may inform our understanding and interpretation of the study findings. The findings suggest that educational interventions should be directed at individual, collective, and institutional cultural levels. Implications for practice are presented.