Competitive business development is based on the satisfaction of the changeable needs of the clients; therefore the companies must integrate flexibility in decision-making to adapt rapidly their productive system to those changes. Strategic decisions of investment on capacity management are critical in this process considering its long-term financial nature; consequently, it is necessary that they are assessed accurately This document presents the evaluation of these decisions involving the assessment of both operational and financial flexibility in a paper company in Valle del Cauca. In this regard, decisions and criteria were characterized for taking into account the review of specialized bibliography and expert judgment at the time of evaluating them. Finally, the proposed model was exemplified by means of a case study Following this methodology it should be taken into account both quantitative and qualitative criteria for the evaluation of strategic projects of capacity management, being the real option analysis a key element to assess the flexibility of decision.