Snowflake Software, specialist in data exchange solutions via Open Standards, has been awarded a contract by the Ordnance Survey of Great Britain (OSGB) as part of the collaborative, European Commission co-funded i-SCOPE project to provide an open standard CityGML Application Domain Extension review and schema encoding. This work builds on Snowflake’s leading role implementing the International Organization for Standardization (ISO) Model Driven Approach to managed Geography Markup Language (GML) application schema design and optimisation for use in practical applications and web services.