Case study research plays a crucial role in studying the development of the bioeconomy. The versatility of the empirical method coupled with the uncertainty surrounding the bioeconomy concept requires a consistent and comparable application of the method to obtain valid and generalizable results. To stimulate such systematization, we first need to know the state of case studies in bioeconomy research. This article reviews the recent literature with a qualitative content analysis facilitated by systematic text coding. Our results provide an overview of how the narratives of the concept of bioeconomy affect the versatility of the case study research. Based on the low density of the illustrated semantic networks, we conclude that future empirical research on bio-based phenomena should be more transdisciplinary and rely more on cross-sectoral approaches. Further work is also required in developing common research protocols that support transparency and replicability of case studies in the bioeconomy.

The Earth's climate system continues to change at an unprecedented rate and ongoing research underscores the urgent need for rapid progress in global and national adaptation and mitigation efforts. The European Union (EU) aims to become the first climate-neutral bloc of countries by 2050 and aspires to achieve a modern and resource-efficient economy. With that goal, on 11 December 2019, the European Commission (EC) launched the ambitious "European Green Deal". To implement it, on 22 June 2020, the EC established the EU Taxonomy Regulation to ensure the efficient movement of capital toward truly green investments (based on the degree of sustainability of an activity). However, there is currently no consensus on what should be assessed and how, which lead to different interpretations and meanings of sustainability performance as well as information inefficiencies that complicate and impair investment into facilitating green transactions. This thesis aims to contribute, through innovative approaches and methods, to a more detailed and careful evaluation of alternative paths to sustainable innovation that apply technologies and social practices based on bio-based materials to transform or re-design conventional production systems (namely, circular bioeconomy systems).Given the complexity and heterogeneity of bio-based systems, the literature contains several coexisting narratives on bioeconomy. After the introduction, the thesis begins by systematically reviewing the versatility of empirical studies-notably, case studies-along with the narratives surrounding the bioeconomy concept (i.e., an ecological economy, a science-based economy, and a biomass-based economy). The results of Chapter 1 provide an overview of how the narratives of the concept of bioeconomy affect the versatility of the case study research. Based on the low density of the illustrated semantic networks, we conclude that future empirical research on bio-based phenomena should be more transdisciplinary and rely more on cross-sectoral approaches. Further work is also required in developing common research protocols that support transparency and replicability of case studies in the bioeconomy.Building on the knowledge gained from this literature review, the thesis discusses three concrete cases, with both scientific and practical implications, of sustainability performance assessments. These studies capture the heterogeneity and complexity of bio-based systems, which differ in terms of feedstock, level of technological maturity,