A system and methodology for cross language type system compatibility is described. In one embodiment, for example, a system for translation of data types between a first application in a first language and a second application in a second language is described that comprises: a formal mapping between data types of the first language and data types of the second language; translators for translating data types between the first language and the second language based on the formal mapping; a translation mapping to the translators based on actual data types of the first application and formal data types of the second application; and a module for selecting an appropriate translator for translating between a particular data type in the first language and a data type in the second language based on the translation mapping in response to invocation of a method of the first application with the particular data type.