The following article presents the results of a study investigating employment of private and non-governmental organisations in Polish municipalities as providers of versatile public services and the resulting nature of the relationship among the latter. The passing of legislation that requires or allows delivering public services through non-public entities triggered the development of a contract culture in municipalities. The resultant relationship may be either of a competitive (mainly technical services market) or cooperative (social services) nature. The research findings support the hypothesis that larger municipalities have better developed processes of contracting public services.