In January 2008 the Land Administration Domain Model (LADM) was submitted as a new working item proposal to the International Organisation for Standardisation (ISO). The proposal includes a draft version of the LADM defining a model covering bothadministrative/legalandspatial/surveyingcomponents of land administration. The standard provides a conceptual schema with basic packages relating to “persons”, “immovable objects”, “rights/responsibilities/restrictions”, “surveying” and “geometry/topology”. The standard model covers the common aspects of cadastral registration in various national and international systems and is as simple as possible to optimise its practical use. This will allow harmonisation through a core model of the differing practises and procedures in different jurisdictions, thereby enabling cross-border sharing of cadastral information. The LADM is designed not to interfere with national land-administration laws.

The motivation behind these standard­isation efforts includes meaningful exchange of information between organisations and efficient component-based system development by applying standard­ised models. Cadastral data is initially collected, maintained and disseminated in a distributed environment, which means that data can be maintained by various organisations such as municipalities or other planning authorities, private surveyors, conveyancers and land registrars, depending on local traditions.
Standardisation in the land-administration domain would help (geo)ICT vendors, allowing them to invest effort in the development of a (generic) system based on concepts described in UML class diagrams rather than focusing on a single cadastral organisation. This would stimulate the availability of generic (object-oriented) standard software from multiple (geo-)ICT vendors, from which cadastral organisations might make a selection, thus providing them with the fundament of new systems. So that they would not need to develop everything from scratch, only local modification and extensions.

STDM
The Social Tenure Domain Model (STDM) is a specialisation of LADM, which is considered designed for areas withformal cadastre and land registry systemsand contains the functionality for the STDM but under incorrect terminology. Many countries have incomplete or absent land administration. Formal terminology as used in the LADM, such as Parcel, Right, LegalDocument, Restriction and RegisterObject cannot be applied in an informal environment. In the STDM the same classes are used as in LADM, but under different terminology. For example, a RegisterObject is named SpatialUnit and an RRR is called SocialTenureRelation. Standardisation of the LADM includes the STDM and is most relevant for practitioners in developing countries. The STDM is recognised by UN Habitat as a pro-poor land tool.

Vote
This is the first time a semantically meaningful domain model has been submitted as a new working item proposal to the ISO Technical Commission 211 on Geo­graphic Information/Geomatics. FIG thinks that key domains like this should be subject to ISO standardisation. The voting on standardisation of the LADM will close on 1st May 2008. If the vote is carried we plan to have the first project team meeting in Copenhagen, Denmark in May. FIG hopes to findsupport for this important development.