Small and medium size enterprises (SMEs) play an important role in the economic growth of emerging countries. However, their environmental impact on ecosystems and population should not be neglected. A review is made of existing methods of environmental diagnostic. A new one is proposed to assess the capacity of enterprise managers to access to environmental information and use it in their technical, administrative, economic, social and decisional structures. It has been used to estimate obstacles and catalysts of integration of the environment in six Tunisian enterprises. Industrial managers who have been interviewed consider environmental integration as a strategic factor which may help them to improve their relationships with public authorities, therefore environment is rather well integrated in their decisional structure. Because of a search of optimization of production equipment, the economic structure is also generally well controlled. On the other hand, their main weak point lies in their social structure. This is mainly caused by a cultural gap between management and workforces and lack of intermediaries. Some communication dysfunction between public and private actors have also been noted. This method could be used to make enterprises aware of environmental stakes as well as to help local communities to define industrial risk for the environment and enterprises needs in order to target their environmental protection programs.