Geo portals make map and feature services accessible and are the front end to spatial data infrastructures. This requires that all services follow the same standards, in the case of maps and geometric features as specified by the OGC.
Loosely coupled service infrastructures are currently hyped as the "Web 2.0". Although this concept is not exactly revolutionary it does get more recognition due to some prominent examples. The broad accessibility of geodata is new. It has been made possible thanks to WorldWind (NASA), GoogleEarth and -Maps (Keyhole), Virtual Earth (Microsoft) and similar services. But except for WorldWind all these are proprietary, closed solutions that provide access only through their own interfaces. The WhereGroup implements Geo Portals that are open and accessible to all world leading GIS systems that support OGC specifications.
The value of Geo Portals is not measured by the quantity of geodata that it makes accessible but in the added value that is generated by overlaying this geodata with other, sometimes highly specialized sets of spatially enabled data. These are registered with the geo portal in metadata repositories and catalogs. The applications of the portal are designed to overlay, query, analyze and in some cases also edit and maintain the data.
As an example of what can be done have a look at the Geoportal-RLP. It was launched in January 2007 to serve as information and communication platform for geodata, geo information and geo related services in Rhineland-Palatinate.

More often than not, availability of geo data proves to be crucial for the administration, businesses and citizens alike. Spatially related information represents a key commodity and serves as the basis for decision making in a variety of different areas.
Portals, in their capacity as an information and communication platform, contribute to the efficient use and application of geo information.
GeoPortal.rlp is designed to act as a broker between users and providers of geo data, geo information and geo-related services. Apart from offering central access to geospatial data in Rhineland-Palatinate, the portal also serves to ensure the provisioning of geo related services as well as geo specific applications and scenarios (e.g. coordinate transformation, data visualization and distribution).
Geoportal-RLP offers the opportunity for both federal state agencies and municipal authorities to present their data and services. Online access to the distributed data sources of all geo products, and vendor neutral interfaces to service providers, ensures that information made available by these institutions on a joint platform is as up-to-date as possible.
The geo portal is embedded in the federal GDI-DE, and at the European level connects seamlessly into the emerging INSPIRE platform. All services provided by the neighbouring state of North Rhine-Westphalia through the GDI-NRW platform can be combined with data from Rhineland Palatinate.