The need to enrich a fast, high volume data stream with slow-changing reference data is probably one of the most wide-spread requirements in stream processing applications. Apache Flink's built-in join functionalities and its flexible lower-level APIs support stream enrichment in various ways depending on the specific requirements of the use case at hand. In this webinar, I like to provide an overview of the basic methods to enrich a data stream with Apache Flink and highlight use cases, limitations, advantages and disadvantages of each.