This paper treat engineering change in two empirical cases and compare them to the literature on the subject emphasizing operation management. The cases, one in an engineering-to-order project in the offshore wind farm industry, the other a production system redesign to accommodate new products for lightweight materials, were both followed using action research principles. The results show that engineering change management principles was not followed in any larger extent in neither case. Furthermore, the literature review showed that the research body rather focus on processes for more stable change processes than practical methods, suitable for engineering-to-order projects and radical changes.