Objectives This study aims to elucidate determinants for succesful implementation of the Enhanced Recovery After Thoracic Surgery (ERATS) protocol for perioperative care for surgical lung cancer patients in the Netherlands. Setting Lung cancer operations are performed in both academic and regional hospitals, either by cardiothoracic or general thoracic surgeons. Limiting the impact of these operations by optimising and standardising perioperative care with the ERATS protocol is thought to enable reduction in length of stay, complications and costs. Participants A broad spectrum of stakeholders in perioperative care for patients with lung resection participated in this study, ranging from patient representatives, healthcare professionals to an insurance company representative. Interventions Semistructured interviews (N=14) were conducted with the stakeholders (N=18). The interviews were conducted one on one by telephone and two times, face to face, in small groups. Verbatim transcriptions of these interviews were coded for the purpose of thematic analysis. Outcome measures Determinants for successful implementation of the ERATS protocol in the Netherlands. Results Several determinants correspond with previous publications: having a multidisciplinary team, leadership from a senior clinician and support from an ERAS-coordinator as facilitators; lack of feedback on performance and absence of management support as barriers. Our study underscores the potential detrimental effect of inconsistent communication, the lack of support in the transition from hospital to home and the barrier posed by lack of accessible audit data. Conclusions Based on a structured problem analysis among a wide selection of stakeholders, this study provides a solid basis for choosing adequate implementation strategies to introduce the ERATS protocol in the Netherlands. Emphasis on consistent and sufficient communication, support in the transition from hospital to home and adequate audit and feedback data, in addition to established ...