David G. Hendry

Errors in the data, formulas, or manipulation of spreadsheets could be costly, even devastating.

Spreadsheets can be considered to be the world's most successful end-user programming language. Spreadsheet formulas are Turing complete.

This early spreadsheet, a Babylonian clay tablet c.1800 BC, contains several errors. How many errors do your spreadsheets have?

See our bibliography of spreadsheet best practice, risk management, errors and testing, and methods for improving spreadsheets.

We are conscious of very few of our errors. When people are confronted with their actual error rates, they are typically shocked.

"Oh My God" my formulas are not working! This article covers most of the reasons for Excel formulas not working. And how to fix them.

Do you document your spreadsheets? We use the FizzBuzz word game to illustrate the importance of documenting your spreadsheets.

Spreadsheet errors are reduced by using good design. Our students do three assignments to acquire good spreadsheet design skills.