ISO 9001 is a standard for quality management systems while CMMI is a model for process improvement. If an organization that has achieved ISO registration wishes to improve processes continuously, CMMI can be a strong candidate because it provides a more detailed roadmap for process improvement. However, with respect to adopting CMMI in organizations that are familiar with ISO 9001, there are some issues that need to be resolved. For example, ISO 9001 and CMMI have different targets, intent, and quantity of detail. In this paper, we present an integrated model of ISO 9001:2000 and CMMI, which would resolve the above problems. We expect that this model will be a useful tool for ISO registered organizations aim to attain higher CMMI levels.