## 5 Concluding Discussion
### Translators, Frontrunners, and Drivers of Policy Development  
In this paper, we identify that national policy ambition plays an important role in carbon emission reduction ambitions, although in some contexts (the US and Australia cases), regional (state) policy is more prominent. All studied cases were positioned in a learning and development context of improving carbon emission reduction ambitions, driven by the Paris agreement, but the strategy varied between the countries. Based on the three-folded categorization of projects roles, based on the approach by [PERSON] and [PERSON] [37] (see Section 2: analytical point of departure), we categorized the projects as translators, frontrunners, and drivers, in relation to their ambitions toward carbon emission reductions (see Table 5 for an overview). Translator: the project aligns with state/regional policy and implements already developed processes. Frontrunner: the project aligns with state/regional policy and drives development processes in industry development. Driver: the project has a higher project ambition than the state/regional policy and drives goals for carbon emission reductions.  
In the United Kingdom, Netherlands, and Sweden, the national governments had clear goals and had initiated various types of agreements and collaborations between state authorities and the industry, including structures for reduction of carbon emissions at a project level (e.g., different types of calculation tools). This shows that in these countries, the power, and legitimacy, of a state actor, including the formulation of clear goals and mechanisms to reach them (the development of calculation tools), play a central role in the implementation of carbon emission reductions [37]. The projects in the Netherlands and Sweden can be categorized as translators of policy; they follow the policy goals and work slowly to push emission requirements down. However, the two UK projects studied took an active part in industry initiatives and acted as frontrunners in driving the development of various collaborative innovation processes at an industry level. In the two US projects, explicit directives were lacking, and the projects chose to set high targets and refer directly to overarching international goals. They both had a high ambition and interviewees used wordings such as \"raise the level for the industry\" and \"take sustainability stewardship\", which categorize them as drivers. Similarly, in the Australian projects, the client had highly sustainability ambitions and wanted \"to leave a transformative legacy\" and \"change the industry.\" The requirements used could, however, be backtracked to the regional policy level. These projects were therefore categorized as frontrunners. It is clear from the study that although frontrunners do not formally raise CO2 reduction goals, they perform an important role in developing actual sustainability performance at an industry level, which can later lead to more ambitious carbon emission reduction goals. This further indicates that ambitious international goals are influential at an industry level and central to reaching high carbon emission reductions in the long run.  
Previous research has also shown that there are multiple pathways for policy implementation depending on the national context [31]. This means that a translator can have more ambitious goals than a driver and frontrunner. Moreover, a frontrunner could achieve a more significant change than a translator by focusing on strengthening industry-level collaboration and engagement.