The changing field of Information and Communication Technology (ICT) has resulted in the development of different applications that are based on heterogeneous platforms, standards and architectures. Thus, the majority of the public sector organizations confront significant problems with information sharing and business process automation and integration. Enterprise Application Integration (EAI) has emerged as a set of technologies to address the issue of integrating the public sector ICT infrastructure, enterprise application integration is the combination of different technologies such as ebXML, CORBA and COM /DCOM However, none of these technologies assert to be a solution to overcoming all integration problems. In exploring the evolution of public sector ICT infrastructure. The evaluation framework is empirically tested within a case study. This can provide the supports to the management of public sector organization while taking the decision to integrate their ICT infrastructure.