OBJECTIVES: To examine the experiences of clinical and managerial leaders in the English healthcare system charged with implementing policy goals of openness, particularly in relation to improving employee voice. DESIGN: Semi-structured qualitative interviews. SETTING: National Health Service, regulatory and third-sector organisations in England. PARTICIPANTS: Fifty-one interviewees, including senior leaders in healthcare organisations (38) and policymakers and representatives of other relevant regulatory, legal and third-sector organisations (13). MAIN OUTCOME MEASURES: Not applicable. RESULTS: Participants recognised the limitations of treating the new policies as an exercise in procedural implementation alone and highlighted the need for additional 'cultural engineering' to engender change. However, formidable impediments included legacies of historical examples of detriment arising from speaking up, the anxiety arising from increased monitoring and the introduction of a legislative imperative and challenges in identifying areas characterised by a lack of openness and engaging with them to improve employee voice. Beyond healthcare organisations themselves, recent legal cases and examples of 'blacklisting' of whistle-blowers served to reinforce the view that giving voice to concerns was a risky endeavour. CONCLUSIONS: Implementation of procedural interventions to support openness is challenging but feasible; engineering cultural change is much more daunting, given deep-rooted and pervasive assumptions about what should be said and the consequences of mis-speaking, together with ongoing ambivalences in the organisational environment about the propriety of giving voice to concerns.