Introduction: A new regulatory framework (the Quality Improvement Regulation) to support local, management-based quality and safety efforts in hospitals was introduced to the Norwegian healthcare system in 2017. This thesis explores healthcare regulation and resilience through the Quality Improvement Regulation, by investigating its possible links to adaptive capacity in hospital management of quality and safety enhancing activities. The literature lacks studies exploring how regulation and resilience intertwine, two concepts often considered as counterparts. Hence, there is a gap in knowledge about regulatory and supervisory impact on quality and safety, and attention to hospital managers’ competences and responsibilities as key elements to resilience in healthcare. This thesis therefore casts a new light on how regulators and inspectors may design, inspect, and enforce a regulation regime, and thereby contribute to adaptive capacity, anticipatory capacity, and learning as key elements in different hospital contexts. Overall outputs from this thesis are important to the development and implementation of future regulatory amendments. Aim: The overall aim of this thesis was to explore the rationale, expectations, implementation, and management of the Quality Improvement Regulation. The overall and leading research question was: How does a new healthcare regulation implemented across three system levels contribute to adaptive capacity in hospital management of quality and safety? Methods: The study was designed as a multilevel, single embedded case study. Data was collected by approximately 500 pages of documentary evidence, 29 individual interviews and 3 focus group interviews (10 participants): in total 39 participants. Data was analyzed by legal dogmatic and qualitative content analysis. Three levels of stakeholders were included from the Norwegian healthcare system: macro-level (three governmental regulatory bodies), meso- level (three County Governors), micro-level (three hospitals retrieved from two regional health authorities). Macro-level participants were seven strategic participants positioned at the Norwegian Ministry of Health and Care Services, the Norwegian Directorate of Health, and the Norwegian Board of Health Supervision. Meso-level participants were two chief county medical officers, three assistant chief county medical officers, and seven inspectors, recruited from three County Governors. Micro-level participants were 20 hospital managers or quality advisors selected from different levels at three hospitals. Findings: Paper I (macro-level) explored the governmental rationale for developing the Quality Improvement Regulation, expectations towards hospital management and its expected influence on resilience. Data retrieved from documentary evidence and individual interviews indicated that the rationale for the Quality Improvement Regulation’s design was to make it flexible to various hospital contexts. In turn, the macro-level expected hospital managers to anticipate local risks. However, the study found that the Government expected the generic regulatory design to come across as challenging for hospital managers and clinicians. Paper II (meso-level) investigated into changes in the supervisory approach and inspectors’ work to promote or hamper adaptive capacity and learning in hospitals. Evidence emerged from documents and focus group interviews and indicated that despite supervision being adapted to specific hospital contexts and the inspectors’ trade-offs, there was a general concern about the lack of impact of supervision on hospital performance. Paper III (micro-level) explored hospital managers’ perspectives on implementation efforts and the following work practices, to understand if, and how, the new Quality Improvement Regulation influenced quality and safety improvement activities. Across interview data, participants experienced the Quality Improvement Regulation as more suitable to variation and different contexts compared to the previous regulatory framework. However, findings revealed no change in practice related to quality and safety activities, solely due to the new regulatory framework, despite recent structural and cultural changes to quality improvement systems in hospitals. Data reported that lack of time, competence and/or motivation affected hospital implementation. Conclusions: This thesis represents a rare glimpse into regulatory implementation efforts across three system levels, set out in a resilience in healthcare perspective. This thesis revealed that regulators considered the perspective of variation, complexity, and uncertainty in hospital settings to be important when designing the Quality Improvement Regulation. The latter resonates with resilience in healthcare concepts and contradicts previous research. The Quality Improvement Regulation contributed to context adaptation, by supporting nondetailed risk based organizing and management of quality and safety. However, hospital managers’ autonomy and adaptive capacity to tailor quality improvement efforts were imperative for the regulatory requirements to have any relevant impact on hospital practice. Limited involvement of clinicians in the regulatory development process could hamper quality improvement efforts. Inspectors could nurture learning by improving their follow up, use expert inspectors, and add more hospital self- assessment activities. This thesis highlights the importance of ensuring that any macro-level quality improvement initiatives and regulatory requirements are accompanied by appropriate resourcing, support, and advanced preparation to ensure the best possible chance of getting implemented effectively.