The Business Strategy describes the business principles, goals and objectives that drive the Enterprise Architecture.
The Business Strategy also includes details of Business Products and Business Services that an organisation offers to its customers, in various markets, customer segments and channels.
The Business Strategy is further defined with a description of the organisations Target Operating Model.
The Enterprise Architecture represents a link between the business strategy (and IT strategy) and the operational systems that are acquired or developed and executed in production.
The Business Principles are the most important drives that shape and govern the Enterprise Architecture and the Solutions acquired or built by delivery projects.
The Enterprise Architecture Principles specifically concern the Enterprise Architecture and there will include separate architecture principles for each Architecture Domain (e.g. Business Services, Process Architecture, Information Architecture, Application Architecture and Technology Architecture).
The organisation's Vision is a statement of the primary goals and objectives desired in the future.
Target Operating Model
The target Operating Model, describes the way the organisation will operate in order to do business.
The ultimate goal of an Operating Model is to define the optimal way to organise the delivery of products and business services and value to clients in the context of other aspects of the Business Strategy such as quality, cost and risk point of view.
See also Wikipedia:Operating Model
Linking Business and IT Strategies
This is where the need to reduce the impedance mismatch is most critical as any misalignment at this stage have long term consequences. In order to mitigate inherent risk associated in this process, agility and iteration can play a vital role. Current business dynamics mandates maintaining balance between 'conformance' and 'performance', which means the right approach exist somewhere between Waterfall and XP.
Two important tools to grasp, position and start off the mapping process are: Benson and Parker's square wheel and Porter's Value Chain Model. Porter's model is specially useful in identifying critical business processes which can then be mapped over by related information systems. Every organization needs to have its own version of Porter model and should iteratively expand on it. It will the linkage between the unique set of business processes employed by a company and supporting information systems which provides strategic position and extended value.
Credit to the author : Adrian Campbell