Purpose - The purpose of this paper is to investigate four dimensions of how to integrate quality in the public procurement process from three perspectives. The study was carried out in the public transportation industry where service provision has been outsourced. Design/methodology/approach - An explorative case study was carried out using two data collection methods. The first involved a document study that considered the integration of quality in the public procurement process. This led to the second method, which involved conducting in-depth interviews to follow up on the procurement and the role of quality with the participants. Findings - The findings provide insights into how quality can be included in the public procurement process and, in particular, how self-assessment can be used to evaluate the "best quality practice". The quality maturity of the industry also has an influence on three dimensions: the choice of quality model, the weighting between price and quality and how the tenders perform their self-assessments. Research limitations/implications - The study focuses on one case and presents explorative findings. This has implications for future research, for which the set of procurement decisions regarding the integration of quality must be analysed. Practical implications - The integration of quality in the public procurement process involves choosing a future business partner according to the "best quality practice", not just the lowest price. Including quality in the public procurement process can help facilitate the delivery of high-quality services to customers when service provision has been outsourced. Originality/value - This study contributes to the service quality literature by empirically investigating how quality can be integrated in the public procurement process, which is a prerequisite for contracting a desired service supplier