Sustainability is more than ever a central concern when deciding a company’s strategy. Stakeholders are continuously pressuring industries to further reduce their environmental impact. In order to achieve that, it is imperative to look for solutions across all of the company’s operations adopting a supply chain view. However, supply chains’ complexity makes this a challenging task. Analysing the sustainability of such complex systems requires the use of capable tools as are optimization models. Several of these models can be found in the literature, mostly focusing on specific issues or specific decisions in the supply chain. Therefore, a research gap is found in models capable of handling a wider variety of decisions. With this work a mixed integer linear programming model is used to demonstrate the impact of including more or less options/decisions on design and planning decisions, and on the environmental performance of a supply chain. A case-study based on a Portuguese pulp and paper company is analysed. The results obtained for different scenarios are examined.