This thesis engages in its theoretical part description of the process of pursuance and assurance of quality in emergency medical dispatch centre. There is also a comprehensive description of key quality parameters used in this environment in this part. The content of the empiric section is an organizational case study, which aim was to evaluate an extensive organizational change in emergency medical dispatch centre of the Emergency Medical Service of the Central Bohemian region and its impacts on the quality of care. The first phase of centralization of emergency medical dispatch centres in the Central Bohemian region went through during the first half of 2011. Four local emergency medical dispatch centres were gradually brought together into one entity. The aim of the research was to evaluate impacts of the organizational change on key quality parameters. The observational retrospective study consists of two groups of data, collected from identical area during two equivalent periods. Group A contains data from the period of six months before and group B contains data from the period of six months after the centralization. Key quality indicators were compared in both groups: response time; call processing times; safety of classification and indication of calls; use of dispatch life support and...