Abstract Background Health services are complex and challenging structures, including diagnostic services. Therefore, it is everyone's responsibility to ensure patient safety. The scope of this study is to present the challenges and opportunities in structuring the Quality Management and Patient Safety System (QM&PS) of a large diagnostic service that culminated in the first laboratory to receive the Patient Safety Core Recognition Seal (NSP), a program established by the partnership of QGA (Quality Global Assurance) and IBSP (Brazilian Institute for Patient Safety). Methods The restructuring of the QM&PS began in 2018 and since then, 6 NSPs have been established, distributed across 6 regions of the Brazil, with procedures, regulations, confidentiality agreements, and responsibilities clearly defined. The NSP are multidisciplinary and discuss 13 safety indicators monthly, namely: adverse events, contrast extravasation, falls and faints, reactions to medications, contrasts, and vaccines, immunization errors - vaccine application and exchange, loss of noble samples, technovigilance, and pharmacovigilance. With an engaged and participative Medical Board, the Patient Safety Committee was created in 2020, with the participation of top management and representatives of strategic leaderships to discuss cases of serious adverse events and deaths with systemic outputs and plans. In 2022, we conducted the first Patient Safety Perception Survey, from which we extracted insights to further develop the safety culture. Six working groups were organized focusing on interaction between company committees and programs, institutional communication for sharing information and Patient Safety initiatives in the organization, identification, prevention, and monitoring of incidents, risk management tool for analysis of clarity, application, and relevance of use as support for management and continuing education. Results The working groups involved 58 professionals and resulted in 65 implemented actions. Among the main results achieved, we can highlight the implementation of the rapid response flow to SAE (serious adverse event), Just Culture Policy, Disclosure Protocol, Second Victim Care Flow, Safety Rite in Customer Service Units, Patient Safety Trail, Institutional Communication, and the Patient Safety Core Recognition Seal. Conclusions Patient Quality and Safety must be part of the institutional pillar, composing the Strategic Objectives to be achieved. It is necessary to engage the organization and rely on the involvement of leadership and physicians. As a large service, our biggest challenges are demonstrating the effectiveness of implemented improvement actions in the face of identified risk modifications, defining strategies to reduce underreporting, and being able to involve all collaborators and operational teams in the safety culture.