Marco Russo and Alberto Ferrari cofounded sqlbi.com, where they regularly publish articles about Microsoft PowerPivot, DAX, Power BI, and SQL Server Analysis Services. They also speak regularly at major international conferences, such as TechEd, Ignite, PASS Summit, and SQLBits. Both consult and mentor on business intelligence (BI) and Microsoft BI technologies, having worked with them since 1999. Their books include Microsoft Excel 2013 Building Data Models with PowerPivot, Microsoft SQL Server 2012 Analysis Services: The BISM Tabular Model, and Microsoft PowerPivot for Excel 2010: Give Your Data Meaning.