Abstract: A system and method is described for event-driven data transformation. Generally, the system and method is directed to a transformation engine that iterates through one or more data sources, transforms data received from the data sources, and stores the output to one or more data targets. More specifically, the transformation engine is driven by executing specified event actions upon occurrence of specified triggering events. Thus, flexible, adaptable, highly tailored transformations can be implemented without incurring the often substantial expense of developing customized point-to-point solutions from scratch. The present invention supports one-to-one, mappings, many-to-one mappings, one-to-many mappings, and many-to-many mappings. In addition, the present invention supports both hierarchical and flat data sources and targets.