THE ARCHITECTURE AND DESIGN OF A COLLABORATIVE ENVIRONMENT FO R SYSTEMS DEFINITIO N Minder Chen, George Mason University and Jay F. Nunamaker, Jr . , Defining systems requirements and specifications is a collaborative effort among managers, users, and system s developers . The difficulty of systems definition is caused b y the human's limited cognitive capabilities, that i s compounded by the complexity of group communicatio n and coordination processes . Current system analysi s methodologies are first evaluated regarding to the level o f support to users . Since systems definition is a knowledge - intensive activity, the knowledge contents and structure s employed in systems definition are discussed . For any large - scale system, no one person possesses all the knowledg e that is needed, therefore, the authors proposed a collaborative approach to systems definition . The use of a group decision support system (GDSS) for system s definition is first described and limitations of the curren t GDSS are identified. The architecture and design of a collaborative computer-aided software engineering (CASE ) environment, called C-CA SE, is then discussed. C-CA S E can be used to assist users in defining the requirements o f their organization and information systems as well as t o analyze the consistency and completeness of th e requirements . C-CA SE integrates GDSS and CA SE suc h that users can actively participate in the requirement s elicitation process. Users can use the metasystem capabilit y of C-CA SE to define domain specific systems definitio n languages, which are adaptable to different system s development settings . A n example of using C-CA SE in a collaborative environment is given . The implications C- CASE and the authors' ongoing research are also discussed . Keywords : Computer-Aided Software Engineerin g (CASE), Group Decision Support Systems (GDSS) , Systems Development, Systems Analysis and Desig n ACM Categories : D .2 .0, D .2 .1, H .1 .2, 11 .2 .4, K .6 .1 , K .6 .3 1 INTRODUCTIO N Systems development is a collaborative effort amon g managers, users, and system developers . It has bee n recognized as a process which acquires expertise fro m multiple experts (Henderson, 1987). Domain specifi c knowledge about an application and its environment, a s well as technical knowledge about systems development , have to be incorporated into a cohesive framework to mak e the target system operable . Many people need to b e involved in the systems development process because no one person can possess all the knowledge required . Th e complexity of the dialogue among people who involved ha s always been identified as one of the major factors whic h causes the failure of information systems projects . 22 DATA BASE Winter/Spring 1991 University of A rizona Tucso n A study has shown that face-to-face meetings can b e important in the software development process (Cook et al ., 1987) . Users, managers, and developers can use grou p meetings to communicate and elicit information an d knowledge, to create alternatives, to resolve disagreements , to reach consensus, and to make design decisions . Unfortunately, systems development meetings are usuall y not well focused, and often fail to reach conclusions . This is partly due to miscommunication, caused by the divers e backgrounds and viewpoints of the participants . For a complex and large software project, the participation o f users and managers is critical to a project ' s success . A s interactions among individual members is very time - consuming and sometimes unfeasible, structured method s and computer systems to support project meetings becom e essential for the full participation of project members . While the need exists, we have found that most syste m development methods do not directly support grou p interaction in a face-to-face setting . Joint Applicatio n Design, a method to facilitate systems design meeting s developed by IBM, is an exception (Wood and Silver , 1989), Computer-Aided Software Engineering (CASE ) tools, which are usually based on structured methods, do no t explicitly provide a mechanism to facilitate meetings of a software project (Chen, Nunamaker, and Weber, 1989) . Thus software project meeting support is a critica l component missing from the existing CASE products . In Section 2, the authors analyze the complexity o f systems definitions and classify tools which can be used t o support systems definitions . The systems definition of an y large-scale system project is a knowledge-intensive activity , thus knowledge contents and structures employed i n systems definition are discussed in Section 3 . The use of a n existing group decision support system (GDSS) to facilitat e the systems definition process is presented in Section 4 . Since there are some limitations of both existing CAS E tools and GDSS tools in supporting the systems definition s meetings, the authors propose an architecture and design o f a collaborative CASE environment, called C-CASE, i n Section 5 . C-CASE is designed to support a project team t o define systems requirements in meetings . An example o f using C-CASE is demonstrated in Section 6 and th e implications of C-CASE to research in GDSS and CAS E are discussed . 2 . TOOLS FOR SYSTEM S _DEVELOPMEN T Complexity of systems definition and inadequacy o f supporting tools always cause delay and errors in softwar e development, There are three major reasons which make th e definition of complicated systems very difficult . The firs t reason is concerned with the inherited bias and the