In fact, many efforts at international level are in progress to define tools in order to make easier the multiple exchange of information in different fields of building design. Concerning this point, protocol and ontology of structured information interchanges constitute the first steps in this sense, e.g. those under standardisation by ISO (STEP), PDT models and Esprit project ToCEE. To model these problems it has brought forth a new research field: the collaborative design one, an evolution of distributed work and concurrent design.

The CAAD Laboratory of Dipartimento di Architettura and Urbanistica per l'Ingegneria has carried out a software prototype, KAAD, based on Knowledge Engineering in the fields of hospital building and of building for aged people. This software is composed by an Interface, a Knowledge Base, a Database and Constraints. The Knowledge Base has been codified by using the formal structure of frames, and has been implemented by the Lisp language. All the elements of KB are objects

Within contemporary digital environments, there are increasing opportunities to explore and evaluate design proposals which integrate both architectural and landscape aspects. The production of integrated design solutions exploring buildings and their surrounding context is now possible through the design development of shared 3-D and 4-D virtual environments, in which buildings no longer float in space.

The scope of landscape design has expanded through the application of techniques such as GIS allowing interpretations that include social, economic and environmental dimensions. In architecture, for example, object-oriented CAD environments now make it feasible to integrate conventional modelling techniques with analytical evaluations such as energy calculations and lighting simulations. These were all ambitions of architects and landscape designers in the 70s when computer power restricted the successful implementation of these ideas. Instead, the commercial trend at that time moved towards isolated specialist design tools in particular areas. Prior to recent innovations in computing, the closely related disciplines of architecture and landscape have been separated through the unnecessary development, in our view, of their own symbolic representations, and the subsequent computer applications. This has led to an unnatural separation between what were once closely related disciplines.

Significant increases in the performance of computers are now making it possible to move on from symbolic representations towards more contextual and meaningful representations. For example, the application of realistic materials textures to CAD-generated building models can then be linked to energy calculations using the chosen materials. It is now possible for a tree to look like a tree, to have leaves and even to be botanicaly identifiable. The building and landscape can be rendered from a common database of digital samples taken from the real world. The complete model may be viewed in a more meaningful way either through stills or animation, or better still, through a total simulation of the lifecycle of the design proposal. The model may also be used to explore environmental/energy considerations and changes in the balance between the building and its context most immediately through the growth simulation of vegetation but also as part of a larger planning model.

The Internet has a key role to play in facilitating this emerging collaborative design process. Design professionals are now able via the net to work on a shared model and to explore and test designs through the development of VRML, JAVA, whiteboarding and video conferencing. The end product may potentially be something that can be more easily viewed by the client/user. The ideas presented in this paper form the basis for the development of a dual course in landscape and architecture. This will create new teaching opportunities for exploring the design of buildings and sites through the shared development of a common computer model.

All three studios tested notions of representation, simulation and the design process in relation to a post-industrial world and its impact on how we design for it. The sites for two of these studios were in the city of Berlin, where the spearhead of the information age and a leftover of the industrial revolution overlap in an urban condition that is representative of our world after the cold war. The three studios describe a progressive shift in the use of information technology in the design process, from nearly pure image-driven simulation to a more low-tech, highly creative uses of everyday computing tools. Combined, all three cases describe an array of scenarios for content-supportive uses of digital media in a design studio. The first studio described here, from USC, utilized computer modeling and visualization to design a building for a site located within the former no-mans' land of the Berlin Wall. The second studio, from SCI-Arc, produced an urban design proposal for an area along the former Berlin Wall and included a pan-geographic design collaboration via Internet between SCI-Arc/Los Angeles and SCI-Arc/Switzerland. The third and last studio from Woodbury University participated in the 1997 ACSA/Dupont Laminated Glass Competition designing a consulate general for Germany and one for Hong Kong. They employed a hybrid digital/non-digital process extracting experiential representations from simple chipboard study models and then using that information to explore an "enhanced model" through digital imaging processes.

The end of the cold war was coincidental with the explosive popularization of information technology as a consumer product and is poised to have huge impact on how and what we design for our cities. Few places in world express this potential as does the city of Berlin. These three undergraduate design studios employed consumer-grade technology in an attempt to make a difference in how we design, incorporating discussions of historical change, ideological premise and what it means to be an architect in a world where image and content can become easily disconnected from one another.

Decisions taken in the ‘private design space’ of the design team or ‘actor’ are closely related to the type of support that can be provided by a Collaborative Design system: automatic checks performed by activating procedures and methods, reporting of 'local' conflicts, methods and knowledge for the resolution of ‘local’ conflicts, creation of new IT objects/ building components, who the objects must refer to (the ‘owner’), 'situated' aspects (Gero and Reffat, 2001) of the IT objects/building components.

Decisions taken in the ‘shared design space’ involve aspects that are typical of networked design and that are partially present in the ‘private’ design space. Cross-checking, reporting of ‘global’ conflicts to all those concerned, even those who are unaware they are concerned, methods for their resolution, the modification of data structure and interface according to the actors interacting with it and the design phase, the definition of a 'dominus' for every IT object (i.e. the decision-maker, according to the design phase and the creation of the object). All this is made possible both by the model for representing the building (Carrara and Fioravanti, 2001), and by the type of IT representation of the individual building components, using the methods and techniques of Knowledge Engineering through a structured set of Knowledge Bases, Inference Engines and Databases. The aim is to develop suitable tools for supporting integrated Process/Product design activity by means of a effective and innovative representation of building entities (technical components, constraints, methods) in order to manage and resolve conflicts generated during the design activity.

Decisions taken in the ‘private design space’ of the design team or ‘actor’ are closely related to the type of support that can be provided by a Collaborative Design system: automatic checks performed by activating procedures and methods, reporting of 'local' conflicts, methods and knowledge for the resolution of ‘local’ conflicts, creation of new IT objects/ building components, who the objects must refer to (the ‘owner’), 'situated' aspects (Gero and Reffat, 2001) of the IT objects/building components.

Decisions taken in the ‘shared design space’ involve aspects that are typical of networked design and that are partially present in the ‘private’ design space. Cross-checking, reporting of ‘global’ conflicts to all those concerned, even those who are unaware they are concerned, methods for their resolution, the modification of data structure and interface according to the actors interacting with it and the design phase, the definition of a 'dominus' for every IT object (i.e. the decision-maker, according to the design phase and the creation of the object). All this is made possible both by the model for representing the building (Carrara and Fioravanti, 2001), and by the type of IT representation of the individual building components, using the methods and techniques of Knowledge Engineering through a structured set of Knowledge Bases, Inference Engines and Databases. The aim is to develop suitable tools for supporting integrated Process/Product design activity by means of a effective and innovative representation of building entities (technical components, constraints, methods) in order to manage and resolve conflicts generated during the design activity.