Dan Keeley is a computer science graduate who started his career in open source BI tools at the very beginning. He has full experience of the entire Pentaho stack and many successful implementations under his belt. He is a well-known Pentaho community member and founder of the Pentaho London Usergroup.

Diethard Steiner, currently working as an independent senior consultant in London, UK, has been specialized in the field of open source business intelligence solutions for many years. He has been very passionate about his work, regularly publishing tutorials on his blog, Diethard Steiner on Business Intelligence (http://diethardsteiner.blogspot.co.uk/), which over the years has gained a loyal following. He has been implementing end-to-end solutions (from data integration to reporting and dashboards) for several clients and projects and has gained a deep understanding of the requirements and challenges of such solutions.