This paper introduces a method for assessment of the maturity of IT Service Management (ITSM) practices in federated infrastructures such as National Grid Infrastructures. Effective ITSM is a key factor in sustainability of federated Infrastructures, allowing them to compete with High Performance Computing and commercial Cloud computing services. By understanding service management maturity through use of maturity models and requirements, e-Infrastructure providers can demonstrate not only the need for improvement but also concrete steps that can be taken to make these improvements.The gSLM project 2 has built up a Use-Case based model of Grid relationships and used this to define maturity levels with matching requirements for each use case. The resulting requirements can be used as an assessment tool, showing an infrastructures maturity level for each use case. This information can be used to highlight problems, recognize successes and plan improvement in service management. The assessment system was used with PL-Grid, the Polish National Grid Infrastructure, in order to validate and tune the analysis method. The results showed that the system format and number of requirements makes it somewhat time consuming but that it provides valuable data that PL-Grid can use to understand their current service offering and make plans on who to improve it. These experiences will be used for an updated version of the analysis framework.