Nowadays, electronic data interchange is an important tool for the partnership between companies from global market competitive sectors. The steel construction industry can also benefit from the collaborative work, through tools developed according to the concepts of the Concurrent Engineering, such as CAD design integrated systems. This work proposes an environment for integration of steel construction design and building planning systems. The basic principle of this environment is to facilitate the relationship amongst the several activities involved, such as the construction planning, the structure project, structural assembly and the cost evaluation. One of the adopted proposition is that the basic tasks of the integrated system are executed by software already available in the market and used in current professional ativities, with the objective of minimizing the impact of the use of this development standard. System modules are integrated by the Internet resources. With the consolidation of the Internet as means of communication and a database as the central point of all the proposed integration, the main task of this work consists on the definition of a data model using an established procedure for the inter-programs communication. Another task is the development of a prototype of the proposed architecture for the several modules integration. Worldwide studies have been made for the development of a complete standard for representation of steel structures data. This work uses the CIS/2 pattern, published for the CIMsteel project, with involvement of several representative organizations of many construction industry areas.