Private Finance Initiative (PFI) is a model of Public Private Partnership (PPP) used to deliver public services which are not commercial in nature. Naturally, clients want to achieve successful PFI projects and they need to have a tool for evaluating the achieved success. Generally there are still no accepted frameworks for assessing project success but several recommendations for development of an evaluation template for assessing the success of PFI schemes exist. To enable success assessment there is a need to identify adequate success criteria. In this paper, important PFI project success criterion for lient called "Starting Date of Operation" will be identified. Model for its application on evaluating PFI project success will be recommended and its empirical applicability on suitable PFI projects in Croatia will be demonstrated. Descriptive statistics indicator will be calculated and referent base for success evaluation of PFI projects in Croatia applying "Starting Date of Operation" success criterion will be established.