Much of the success of projects using Enterprise Modeling (EM) depends more on the quality of the process of modeling rather than on the method used. One important influence on the quality of the modeling process is the competency level of the experts responsible for the EM approach. Each EM project is, however, specific depending on the purpose of modeling, such as developing the business, ensuring the quality of business operations, and using EM as a problem solving tool. The objective of this paper is to discuss the core competency needs for the EM practitioner and to relate those needs to different purposes of EM.