This article examines sustainability accounting (SA) in a French international construction company, viewing it through the frame of being a wicked problem. Sustainability accounting literature often assumes that reporting is a matter of institutional will. It presumes that the necessary key performance indicators (KPIs) already exist, and environmental impact can be measured with confidence. Accuracy, balance, clarity, comparability, reliability, stakeholder inclusiveness, and timeliness are all assumed to be realizable. However, the ethnographic research presented here reveals a very different picture. None of the key criteria were met. The necessary measurement tools were fallible, key definitions were controversial, and making a convincing instrumental or technical choice between relative and absolute accountability was impossible. The failures of sustainability accounting are not attributed to corporate unwillingness or greenwashing. Instead, they are a result of an inability to recognize measurement as a wicked problem. While the wicked problem as a concept is well explained in the literature, ethnographic applications are rare. Therefore, this study makes an additional contribution by demonstrating how the wicked problem concept can be used to frame real-life issues. In conclusion, we ask the question: Has the sustainability accounting literature misrepresented the challenges, ignored the pragmatics of having to deal with wicked problems, and thus failed to be sufficiently accountable itself?