We often have a situation when we need to implement a very complex mappings and need to make use of XSLT mapping with large number of Valuemappings to be maintained for various conversions. One way of implement XSLT is at Design time as mentioned in the blog Design time Value-mappings in XSLT (Design time Value-mappings in XSLT). But if we need to maintain very large number af enteries, and data changes very frequently we need to look for alternative, as it is difficult to maintain the data at design time. We can make use of runtime valuemapping to achieve this. We can maintain data in same way as we do it while using valuemappings in Message Mapping (by maintaining Value mapping groups in Integration Directory). This Blog explains a simple interface in which we will make use of standard API to use the value mapping entries maintained in Integration Directory. First, We will create a very simple data type, Message type and Messgae Interface for both sender and receiver. i am using same data type for both sender and receivers. create Interface mapping using the Message interface created above. The API which needs for this concept is *aii_map_api. *I assume its available by default on XI server as it was for me :).