Contexts 
SAP Sourcing allows a single implementation to support multiple enterprises, with each enterprise including one or more companies. These enterprises and companies can be set up as separate contexts, each with a different set of business rules and isolated view of data. This section provides a basic introduction to contexts as background for the sections that follow.
The context provides a logical partitioning of the SAP Sourcing data. A single system can be divided into one or more Enterprise contexts, with each Enterprise context containing one or more company contexts. The system is implemented by defining master data at the Enterprise level, and sourcing documents at the Company level. Using contexts in this way, the implementation shares a single set of master data across all companies in the enterprise, but partitions sourcing documents like RFxs so that they are available only to users within a particular company. The System Context is used only for the definition of clusters and contexts.
Contexts, therefore, provide the highest level of data scoping. Since maintaining master data has some overhead, the goal is to leverage a single set of master data for as many users as possible. Unless implementation requirements dictate different master data information, a single enterprise context is typical for most implementations. The segregation of sourcing documents into company contexts provides the most basic level of visibility control and should be considered at initial system implementation based on the desired sharing between business units.
Note
A context represents a separate object from a Company, and that one or more Companies can be associated with a single context. This allows the enterprise to be defined with some Companies sharing access to sourcing documents, and others having segregated data.
Note
Suppliers are implemented by default at the enterprise level. This allows a supplier to be invited to events hosted by any company context within the enterprise. While this gives suppliers broad access to sourcing documents (events), their actual access to events is controlled by the purchaser's invitation, and so their access to the system is properly restricted.
You can only create and configure contexts by logging into the administration portal (/fssystem/portal/login) as the system administrator and selecting Enterprise Contexts on the Setup page. Procedures for creating contexts can be found in the Installation Guide on SAP Service Marketplace (http://service.sap.com).
Once you start to create production data, it is extremely difficult to change decisions about contexts. Deciding how to leverage contexts is a crucial step in planning the implementation, and should be done with careful consideration of future planned use of the system. Throughout this Setup Help documentation, you will see specific references to context scoping as relevant to specific areas of the implementation.