Although people admittedly are one of the most valuable assets of many software companies, relatively little academic research has been done from the well-­‐being at work aspect of software professionals. This intervention study aims to address this gap in prior research by examining the potential effects of using standing instead of sitting workstations on the well-­‐being at work of software professionals in terms of physical activity, mental alertness, and stress. The two measurements before and after the intervention were conducted in June and September 2015 for 29 employees of a local site of a large Finnish software company by using questionnaires and the Firstbeat Lifestyle Assessment service. The findings of the study suggest that using standing instead of sitting workstations results in only modest promotions of physical activity, does not to have an effect on mental alertness, and actually tilts the stress–recovery balance more towards stress, as least at the early phases of usage.