The tools and other resources on WF-Tools.see.tu-berlin.de have been developed by the industrial ecology research group of the Chair of Sustainable Engineering (SEE) at the TU Berlin. The Chair of Sustainable Engineering develops scientific sustainability assessment approaches for products and technologies. While environmental protection and sustainable development are accepted principles for political decision making and corporate strategies, organizations face challenges when dealing with the practical and substantial implementation of the sustainability concept. How can the environmental and sustainability performance be measured in a scientifically robust way, especially with regard to products and manufacturing processes? The SEE group tackles such questions by developing and applying methods and tools with a system perspective on environmental impacts and sustainability performance.