It offers the product and service to the customer, method of thinking of assuming that the respective business such as supply/development/production/sale/service, in the consecutive flow final it directs to the customer consecutively, value and cost with the thing as the considering and this chain activity which & it keeps adding accumulating "value" is produced the enterprise activity that.

Originally, the Michael E porter of the Harvard business college (Michael E. Porter) the professor, book "Competitive Advantage: Creating and Sustaining Superior Performance "(1985) with in the word which is shown, you lectured as the framework which analyzes the internal environment of enterprise in order to make the source of of competitive predominance of enterprise clear.
Value chain(origin: "Of the strategy" country competitive predominance "of competitive predominance")

To divide in consecutive activity it is possible the business which is done inside enterprise. With the value chain model of the porter activity of enterprise, paralleling to the flow of the business which reaches from to high-level downstream as a general structure, "buying physical distribution" "production" "shipment physical distribution" five ' main activities ' "of marketing and sale" "service" and, it supports these main activities "procuring activity" "engineering development" "man-power resources management" "general management () four ' support activities ' such as financial affairs, judicial affairs and information service" it has divided.

It is the subject where this individual activity unit produces value, that activity is called "value activity". And, a certain value activity (head-end process) output becomes input of the next process, consecutive conversion (processing) the system of the interdependence which keeps being done chain is the value chain. The respective value activity needs the resource (the human mono gold), cost occurs. Difference of value and the cost which chain the whole value produces is margin in the upper figure (profit).

Those where value chain analysis disassembles enterprise activity once in individual value activity, grasps the respective added value and cost, whether how it has contributed to the value whose each activity is final, by the concerns and the fact that structure is made clear, the source of competitive predominance (or the possibility) searches. Some activity the importance?, whether it has become the source of competitive predominance, it differs depending upon industry and enterprise.

On that, it should concentrate to which value activity, or whether, cooperation with outside and cooperative relationship is constructed examining and so on it redesigns the value chain. This says the porter, "the strategy" is.

The porter has used the language, value chain vis-a-vis the activity inside enterprise, (the vertical flow to the last customer is called the "value system" from the highest level where the plural enterprise - - value chains are connected). But as SCM and the out-sorcing which receive influencetoconceptof the valuechain, managementconceptualtechnique of core ?????? and BPR etc. appears, the existing value chain dismantling the result IT which supports that developing, in many industries, the relation which jumps over the framework of enterprise has been born. Generally, the business model which utilizes the management resource outside such, there is many a thing which is called the "value chain".