Bob Umlas worked for a major tax and accounting firm, using Microsoft Excel® 8 hours a day, writing custom applications for staff and clients from 1998 to 2018.

He has been using Excel since 1986 - version 0.99 (on the Macintosh)! He was a contributing editor to Inside Microsoft Excel for many years, a magazine devoted exclusively to Microsoft Excel and published by The Cobb Group and later Ziff-Davis. At the time, most issues contain either an article by Mr. Umlas on using VBA (Visual Basic for Applications) or some tip or technique from him on using Excel. He has had more than 300 articles published on subjects ranging from beginner to advanced macros, and on tips, shortcuts, and general techniques using virtually all aspects of Excel.

Mr. Umlas was voted an “MVP” (Most Valuable Professional) by Microsoft each year from 1994-2018 (25 years!) for his contributions to the various online Forums about Excel and is known world-wide for his contributions in Excel. As an MVP, he met yearly with his fellow-MVPs at Microsoft’s headquarters in Redmond, where he had access to the product developers. He has been a beta tester for new versions of Excel since version 1.5, and was asked by Microsoft for his input for newer versions of Excel. In 1995 he led a session called "Maximizing Excel Development Using Array Formulas" at Microsoft's Tech Ed Conference in New Orleans, and he led a session called Tips and Tricks at a Microsoft convention in New York City. He has hosted London’s Global Excel Summit each year since 2021, and in person in 2024, as well as led a session on tips and tricks. He also led a session on tips and tricks at the Las Vegas’ Financial Modeling World Championship in December, 2023. He has led online sessions all over the world including Africa, India, England, Canada and of course, the USA.

He is also the technical editor of many of Bill Jelen’s (Mr. Excel) books. Mr. Umlas used to co-lead the New York PC User's group on Excel every month for about 20 years. He started leading this group again in 2018. He has been teaching Excel to individuals and corporations for several years.