Identifying the processes in the cadastre enables understanding the principles on which the cadastre works and the needs for its improvement. These processes define the way how the cadastre manages information and what are the prerequisites for the data to be stored in the appropriate data structure. The first step in determining the set of processes is defining business tasks in a cadastre that arise from the needs of different users - internal in the cadastre and external, like right holders, the Government and many other organizations. These needs define business tasks and data sets necessary to successfully perform the task. The next step is to define the process itself, and then implement the process in the appropriate architecture. Navratil and Andrew (2004) organize processes in the cadastre in two groups: processes that change the data in the system and the processes by which data are downloaded or viewed. The analysis of business processes in the Serbian cadastre shows that such basic process division is applicable as an initial step in the process hierarchy. A top-down strategy was selected for describing the processes. This strategy increases the decomposition of the process from general to specific, thus creating an insight into the elements of the subsystem. At the highest level, a system overview is defined without the introduction of process details. Each subsequent level introduces more details, or processes, as long as the level specification is not reduced to basic processes or activities. The standardization of specific processes for all cadastres in the world is impossible due to the large differences in the way in which certain procedures are implemented from one country to another. However, the first three levels of the described hierarchical process group division can be applied to cadastral transactions in general. The processes in cadastre can be implemented using the technology of Web services in a Service Oriented Architecture (SOA). The technology of Web services supports automated integration of systems of independent organizations and are in wide use for that purpose. Having this in mind, in this paper we first present a developed model for the processes in Serbian cadastre and then extend it to support data maintenance and transactions in 3D cadastre, including registration and update of 3D spatial units. Considering the ongoing projects in the world on integration of geospatial information with indoor spatial information and building information modeling, we explore the possibilities of implementation of 3D information in the SOA environment. If the information about 3D legal spaces is encoded using buildingSMART openBIM standards we explore the possibility of using these standards including BIM Collaboration Format (BCF), an XML schema and RESTful web service for the exchange of data which is shown on the selected case study of a typical building.