Background Customer satisfaction is important for clinical microbiology laboratories and the most important service aspect is the reliability of responses. One important indicator of the quality of care is turnaround time for a sample referred to a laboratory. Aim This study describes and evaluates an improvement of the blood culture process and evaluates the staff’s experiences of the changes brought by the improvement project. Methods The blood culture process during evenings and nights was re-designed in a cooperation project between the laboratories of clinical microbiology and clinical chemistry in a mid-size Swedish county council. Typing with matrix-assisted laser desorption/ionization time of flight (MALDI ToF) and rapid antibiotic susceptibility testing were also introduced. To describe staff experi-ences semi-structured interviews were performed with twelve of the staff involved. Results The time from sampling to susceptibility testing and typing, for patients with cefotaxime resistant enterobacteriaceae, was before the improvement project on average 55 hours compared to 43 hours after closure of the project. In the qualitative content analysis four categories were found which represented the experience of the staff: patient focus, changed knowledge, cooperation and driving forces. Discussion The study of the implementation of the improvement showed that laboratory staff could handle the change well. The change from traditional biochemical typing, used for over 50 years, to MALDI ToF is indeed a paradigm shift. Nevertheless, nobody was disappointed over the fact that some of the fundamental previous microbiological laboratory work routines were laid to rest.