Every Business Intelligence professional should have a basic understating of the DAX language. Products such as Power BI and Analysis Services have a tabular semantic model that can be extended with custom measures, calculated columns and/or calculated tables. This presentation requires no prior knowledge of the language. The DAX language depends upon the relationships defined between tables in the model. The two different contexts (row and filter) come to play when writing expressions. At the end of the presentation, a professional will have working knowledge how DAX can be applied to a given model.