A computer implemented 
system analysis and design method for use in a complex 
business environment characterized by a set of tightly linked business processes captures in a framework a world view of a business decision and / or a business 
application software system. A world view is defined by 
business objectives, constraints, assumptions, data, and underlying model used in business decision and / or the 
application software system. The framework is used to specify and document each business decision and / or business 
application software system in the complex environment. A BDML (Business Decision Markup Language) is used to implement the framework for specifying the world view of a business decision and / or a business application 
software system. A BDML processor comprises a 
syntax processor that checks the 
syntax correctness and 
syntax consistency within an individual and between different documents written in BDML, a logic processor that checks logical consistency between different documents written in BDML, in terms of the 
business objectives, constraints, assumptions, data, and underlying model among the different documents, and a knowledge-based processor including a 
knowledge base of business decisions, common choices for their decision support models and commercially available decision support systems, the knowledge-based processor providing suggestions for a set of BDML documents to improve consistency using the 
knowledge base.