SYNOPSIS: The dramatic increase in the number of restatements filed over the past years has been attributed to numerous causes, including the complexity of the accounting standards, internal control reviews, changes in materiality thresholds, the overly conservative nature of auditors, earnings management, increased transaction complexity, and the second-guessing of management judgments by a variety of interested parties. However, empirical evidence on the underlying causes of restatements has been lacking. This study provides such evidence by directly addressing these questions: (1) To what causes do companies attribute restatements? (2) To what characteristics of the accounting standards do companies attribute restatements? Relying on the restating companies’ disclosures about restatements, we find that companies most often attribute restatements to basic internal company errors unrelated to any specific characteristic of the accounting standards. We also find that, for those restatements attributed to some characteristic of the accounting standards, the primary contributing factor is the lack of clarity in applying the standards and/or the proliferation of the literature because the original standard lacked clarity. These findings should interest standard setters and regulators addressing the proliferation of restatements and academics using restatements as proxies for constructs of interest in research.