This paper introduces the Telecommunication Outside Plant Markup Language (TOPML), an OpenGis GML (Geographic Markup Language) application schema designed to describe telecommunication outside plant data in which geographical information is an important issue. TOPML uses the standard OpenGis GML schema to include geographic properties to georeferenced telecom network elements. The use of TOPML can be a key factor for cost reduction on data gathering, conversion process of georeferenced data and system integration. By using TOPML, telecom systems can now communicate in different ways such as Web Services. The TOPML can be transformed into an SVG format, allowing geographic data visualization in the Internet. Additionally, with TOPML and the definition of services following the OpenGIS specifications, the telecom outside plant systems can move towards a standard interoperable environment. The results of this paper are being implemented in the CPqD Outside Plant System, a geographical inf...