The presentation will provide an introduction to the concept of epistemic trust and its recent application to developmental psychopathology. Epistemic trust refers to trust in communication or communicated knowledge, and has been implicated in both social learning and psychopathology, as a result of disruptions in the capacity to adopt an appropriate epistemic strategy in relation to social information. These ideas were initially based on experimental work by developmental psychologists but in order to develop a broader empirical basis for this thinking, we have recently created and validated a questionnaire assessing epistemic stance (ES)–the Epistemic Trust, Mistrust and Credulity Questionnaire (ETMCQ). Initial findings will be described that suggest intriguing links between the epistemic stance and developmental psychopathology constructs. Mistrust and Credulity scores were associated with childhood adversity and higher scores on the global psychopathology severity index and both factors partially mediated the link between early adversity and mental health symptoms. Mistrust and Credulity were positively associated with difficulties in understanding mental states and insecure attachment styles. The implications of the theory and these findings will be discussed in relation to psychotherapeutic treatments, particularly in relation to personality disorders and working with groups who have been traditionally labelled as “hard to reach.” Register here