1. An apparatus for coordinating building design comprising: a data memory for storing a three dimensional building model, the three dimensional building model having a plurality of elements, each element having a plurality of attributes; an element ownership processor for assigning ownership of each of the plurality of elements to one of a plurality of users, wherein each of the plurality of users has ownership of a subset of the plurality of elements; an element attribute ownership processor for assigning ownership of a plurality of element attributes for an element to a first user of the plurality of users and receiving a request from a second user of the plurality of users to access one of the plurality of element attributes for the element assigned to the first user and changing a predetermined data field associated with the one of the plurality of attributes to reflect that the second user has an exclusive right to modify the one of the plurality of attributes or is the current owner of the one of the plurality of attributes; a model modification processor for receiving the three dimensional building model and for allowing a user to modify only elements and element attributes that they have ownership of; and a model synchronization processor for receiving only modified elements and element attributes from the model modification processor and updating the three dimensional building model to include the modified elements.