This chapter concerns itself with the application of the concepts presented in chapter 3 to the organization form decision in the procurement area.
First chapter 4.1 regards the procurement and its organization possibilities from transaction-cost-theoretical view, whereby the existence outsourcing and the external service supplying company is explained and justified.
In chapter 4.2 a deepened investigation of procurement costs takes place on the basis the comparison between internal and paged out procurement on basis of the example customer GmbH from it in chapter 4.3 recommendations for action for as efficient an organization of the procurement process as possible is finally derived.

The author wants to begin the application of the theory with by explaining, why the procurement can be seen as transaction and such a view brings which consequences with itself.

The description of the procurement process in chapter 2.3 points on the fact that it is in the final result an exchange relationship between enterprises and suppliers. This corresponds to the definition of transaction of chapter 3.1, i.e. the exchange of a property or a service between transaction partners.
For this reason one can define the procurement process as transaction and examine him regarding the transaction dimensions:

• Procure-specific investments : Thus the extent is meant, in which the contracting parties fall back for the organization and completion of the procurement process to specialized input factors.
  "this happens rather on the side of the suppliers as on that of the customers, since generally each enterprise orients itself at its customer market. (1) location-specific investments, e.g., are mostly transacted by the suppliers, itself after the size, which and the prestige of their customers arrange strength. At the customers such investments are usually small. (2) system dependent investments can occur for example with the organization of the camp, if e.g. the supplied products require special conditions for the storekeeping (refrigerators, etc.).
  Also the use of a specific software can cause relatively high investments. (3) investments into specific human resources refer e.g. to the necessity, in the camp with special and/or to deal dangerous materials or in the office with firm specific work procedures. But one must train the own coworkers or specialized coworkers to adjust. One finds this kind of specific investments in the procurement most frequently. (4) customer-specific investments concern the customers, but the suppliers by definition not. There can be however the case that the customer due to a large order with one its customer more commodity the suppliers necessarily and the camp must extend. In this case a relatively high investment must be transacted. (5) investments in the Reputation serve for the more successful sales and not purchase.
  Therefore they are transacted in the procurement only by the suppliers (see e.g. ISO certifying). (6) date-specific investments in temporally only limits for removable or profitable goods and achievements are transacted, if e.g.. the customers of the procurement customer season goods or just in time produce. This can affect also the relationship with the own suppliers, and high investments cause." ¹⁰⁰
  "although specific investments in the procurement area are transacted rather of the suppliers as of the customers, are them potentially relatively highly. Most specific investments are transacted however for the strategic need and the so-called A-parts. For B and C-parts, which do not exhibit a strategic meaning, however the specific investments are generally small." ¹⁰¹
  Stock management classifies the products on basis of its proportional value on the entire volume of purchase in A -, B and C-parts. The A-parts are goods with high original cost, their proportional value amount to 80% of the volume of purchase. B and C-parts possess however low purchase prices and have at the entire volume of purchase only 20% portion. ¹⁰²
  The relationship is however turned around regarding the portion of the entire number of suppliers.
  Compared with the A-suppliers, who represent approximately 20% of the entire suppliers, B and C-supplier are 80% of the number of suppliers. ¹⁰³
  "therefore it B and C-products bind substantial capacities and this despite low unit price lead to a high process/overhead surcharge." ¹⁰⁴
  Whereupon however in chapter 4.2 is received more exactly.
• Procurement uncertainty :"uncertainty belongs to the everyday life of the transaction" procurement ", independently of whether it concerns A or B or C-parts.
  An enterprise can be uncertain e.g. over the quantity of the products which can be ordered, so that the agreement with the suppliers becomes more complicated. Also regarding prices, possible discounts, delivery times and quality of the commodity there can be uncertainty. Thus a procurement contract can become costly, there it not all circumstances and eventualities consider can."¹⁰⁵
• Procurement frequency :"the procurement process usually very often repets itself. This applies in particular to B and C-parts, those on the average for 80% of allorder procedures constitutes." ¹⁰⁶
  

Tab. 4: The three transaction dimensions regarding the procurement.