This paper investigates which risks characterise radical innovation projects. In-dept case studies were carried out via interviews and a questionnaire. The risk concept applied in this study includes three dimensions: certainty, controllability and impact. Three structural or unambiguous risks were found: new product performance according to specification, reliability of suppliers and new product adoption by consumers. The incidental or ambiguous risks that were found relate to: internal organisation and project management. These results can provide guidance for project teams and innovation managers regarding issues they must seek to tick off early and issues that continuously require team and management attention.