With the emergence of environmental legislations in many countries, the importance placed upon environmental protection has been raised to a new level, especially for industrial activities. Considering environmental issues as early as possible, starting with the design stage, is expected in order to better manage and diminish adverse environmental impact. Commensurate progress has been made in method/tool development for use in environmental impact estimation; however, very few of these methods allow integrating this estimation early in the design process – a critical point of deciding for potential product concepts and suppliers. In this paper, we propose a tool that integrates environmental impact estimation into architecture and supplier identification, in order to conjointly consider requirements satisfaction as well as uncertainty due to new module and new supplier integration. This tool is developed to support OEM (Original Equipment Manufacturer) decision-making in the context of an extended enterprise. A case study is presented to illustrate a plausible implementation.