Business documents directly exchanged between applications usually follow a certain business document standard. No matter whether these standards are traditional EDI standards or XML-based, they are very generic including all elements that may be of need to any company in this world. Before being used in a partnership, a subset of these elements has to be defined based on the business context (geopolitical region, industry, etc.). Usually the definition of these subsets-called Message Implementation Guidelines-starts from scratch, and, thus, is very time-consuming. In this paper we present an approach to explicitly assign context to the definition of Message Implementation Guidelines. This contextual information is also used to calculate a subset for to-be-developed Message Implementation Guidelines based on existing ones. The corresponding approach is supported by a prototype implementation.