This paper depicts the knowledge-based system named as ESPMS (Expert System for Process Model Selection) through various models. A questionnaire was developed to identify important parameters, which were evaluated through domain experts in about all the universities of Pakistan. No exact system was found, which could guide Software Engineers for selection of a proper model during software development. This paper shows that how various technologies like Fuzzy Logic, Certainty Factors, and Analytical Hierarchy Process (AHP) can be adopted to develop the Expert System. Priorities assignments to critical factors have been shown for decision making in the model selection for a problem domain.