## 4 Results
### Industry-Level: Market Development and Leadership
Furthermore, the reduction requirements were open and did not offer any guidance to suppliers regarding what measures to take to reduce their carbon emission impact. The interviewees pointed at the need for industry-wide guidelines and standards and stronger collaboration in the supply chain, to implement carbon emission reduction more efficiently. In addition, the contractors taking part in the roadmap work said that they had the ability to implement more carbon emission reduction measures, but that the requirements were initially set too low to provide sufficient financial incentives for this. In the **UK**, which was preparing large investments in infrastructure, several government initiatives had been taken to support environmental improvement in the infrastructure industry. The base for this work was the 50% carbon emission reduction target put on the sector, which was perceived to require substantial changes. The government actively promoted industry associations and groups, such as the Infrastructure Client Group and the Green Construction Board (2011), to drive development in terms of environmental efficiency and innovation. Government-industry reviews identified performance opportunities, both in the sector in general (Infrastructure Cost Review [47]) and related to carbon emission reduction (Infrastructure Carbon Review [48])). A key statement in the Infrastructure Carbon Review, which was developed by the Green Construction Board with a high level of involvement by Anglian Water, was that \"reducing carbon, reduces costs,\" by saving materials, reducing energy demand, and creating operational efficiencies. A need to establish \"stretching\" targets for carbon impact was emphasized, and traditional standards should be challenged. Furthermore, pursuing a low carbon agenda was seen to stimulate innovation, and performance specifications were recommended over traditional specifications. In the **US** the CHRS project in California had an explicit strategy to leverage market power and raise requirements, to drive innovation in the supplier market over time. There was a concern that too high requirements would limit competition and drive costs. The CHSR project comprised several successive sub-projects, and the client authority clearly communicated that requirements would be raised over time, thereby allowing suppliers to prepare and make investments. Consistency was reinforced by establishing relationships with research and environmental organizations, which then created external expectations on CHSR that would be hard to walk back from. Sustainability policies were established in the new organization early on, to identify meaningful and relevant focus areas. The Sustainability Implementation Plan clarified how the sustainability policy would be integrated into procurement documents. Due to the immature supplier market, the first project started on a very basic level, using \"_if feasible_\" requirements for carbon emission reduction. In addition, requirements for EPDs were for informational use only. In this way, green alternatives had a possibility to develop on the market over the course of several sub-projects. For the steel suppliers, however, some requirements were seen as easy to fulfill, due to previous experience from the building sector, which is ahead of infrastructure. In the SFO project the sustainability requirements were integrated in procurement documents and a workshop was held with the client and the contractor, to establish a proactive approach to the sustainability criteria. The SFO also had sustainability guidelines for planning, design, and construction guidelines that were formed to comply with the set criteria. In this way, the client supports the contractor with the use of new criteria. EPDs for products were used in the SFO project as well, and documentation and information about the materials were critical to fulfilling the aim of low carbon materials from suppliers.