Abstract.  
This paper critically examines the challenges associated with demand for immunization, including the interplay of political, social, economic and technology forces that influence the level of immunization coverage.  In an earlier paper by the same authors, system dynamics modeling and case study research methods are used to capture the complex and dynamic nature of the immunization process. This paper suggests a framework to capture the complex and dynamic nature of the immunization process and tests its effectiveness using a case study on Uganda  healthcare provision. The results indicate in cases of developing nations, immunization demand outstrips immunization coverage.  The   paper suggests that the model and results could be used for theory building in immunization policy evaluation in developing countries.