Jan Gustavson

95% of all spreadsheets contain errors. So, it is almost certain that your spreadsheets are wrong.

A poorly documented spreadsheet erodes effective use. Our workshops help students develop good documentation habits and skills.

Your spreadsheets may be disasters in the making. Strive for spreadsheets that are validated, reliable, and auditable.

Solver Max provides a collection of optimization model examples in Excel (using the Solver and OpenSolver add-ins) and Python.

60% of large companies feel 'Spreadsheet Hell' describes their reliance on spreadsheets either completely or fairly well.

The twenty principles for good spreadsheet practice aims to reduce the amount of time wasted and the number of errors.

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

"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.