Joshua N. Milligan has been with Teknion Data Solutions since 2004 and currently serves as a Principal Consultant. With a strong background in software development and custom .NET solutions, he brings a blend of analytical and creative thinking to BI solutions, data visualization, and data storytelling. His years of consulting have given Joshua hands-on experience with all aspects of the BI development cycle from data modeling, ETL, enterprise deployment, data visualization, and dashboard design. He has worked with clients in numerous industries including financial, energy, healthcare, marketing, government, and services. Joshua has been named by Tableau as a Tableau Zen Master every year since 2014. This places Joshua in a group of individuals recognized by Tableau as not only masters of the tool but also who have a deep desire to teach and help others. As a Tableau Ambassador, trainer, mentor, and leader in the online Tableau community, Joshua is passionate about helping others gain insights from their data. He frequently broadcasts webinars to educate and inform the Tableau community and the world at large about the wonders of Tableau and is a much sought after featured speaker at Tableau conferences, user groups, and various technology and industry functions. He thrives on helping others. Joshua is the author of the first edition of Learning Tableau, which quickly became one of the highest acclaimed Tableau books for users at all levels. He was a technical reviewer of the Tableau Data Visualization Cookbook, Creating Data Stories with Tableau Public, and his work has been featured multiple times on Tableau Public’s Viz of the Day and Tableau’s website. He also shares frequent Tableau tips, tricks, and advice along with a variety of dashboards on his fun and creative blog site. You can follow Joshua on Twitter at @VizPainter.

Tristan Guillevin is a true data lover who likes to share his passion. He graduated from engineering school in 2015. During these years, he went to Burkina Faso to teach computer science in schools around the country. The will to share and help people never left him since then. He started his professional life as a consultant at Actinvision, where he discovered Tableau. Soon, data visualization became a passion that has taken him around the world. In 2017, he won the Iron Viz (the ultimate data visualization battle organized by Tableau every year) in Las Vegas. Since his winning, he helps people with Tableau by making webinars, conferences, blog articles, and finally, this book! He's currently working at Ogury as a business analyst.