**5. Conclusions**

Climate change poses unprecedented challenges for the world's socio-economic and ethical issues of responsibility towards mitigating these impacts. While science is warning of the need to act urgently on climate change (e.g., IPCC AR6 WGII), societies are also responding to global challenges. The United Nations' Sustainable Goals have addressed the whole spectrum of health, poverty/economy, environment, and peace/cooperation. The authors concluded that currently there is a range of risks associated with the implementation of industrial symbiosis. A wise national strategy alongside cooperation with neighboring countries, in particular BUP member states, can result in development of a unified approach to solving the resource efficiency issues as well as to improvement of sustainable competitiveness, material footprint, and also as a consequence, the eco-innovation index.

It is obvious that the circular economy is becoming the new normal and a change in social mindset is crucial, as well as transformation of national legislation that will focus on keeping the existing resources within the economic cycles for as long as possible and avoiding them to become waste. The authors conclude that BUP is a very successful cooperation program which has been developed in the field of education, but it is worth considering the possibility to foster its development and broaden the cooperation fields by, for instance, including a pilot project of industrial symbiosis cooperation.

The matrix for the development of regional or cross-country IS is considered to be a very useful tool for policy makers as well as for potential centers of excellence as it can be applied as a roadmap for decision-making and to facilitate certain practical aspects of regional or cross-country IS development. In future research, the authors plan to provide the developed matrix for approbation in one of Latvia's planning regions in order to analyze its practical application. The authors have developed a range of recommendations based on research that could be analyzed more in-depth within future research namely: development of a cross-country center of excellence on industrial symbiosis and thus summarizing a range of recommendations for policy-makers in order to foster symbiotic exchange at regional and cross-country levels; gathering currently existing best practices of regional industrial symbiosis cases that would form the basis for a comprehensive methodology, so that all the involved stakeholders would be able to see tangible benefits from this business model and become economically engaged in fostering its implementation.

**Author Contributions:** Conceptualization, D.A., N.C.-P. and M.P.; methodology, D.A.; software, M.P.; validation, D.A., V.K. and O.T.; formal analysis, P.N.; investigation, O.T., D.A. and M.P.; resources, D.A.; data curation, V.K.; writing—original draft preparation, N.C.-P., D.A. and V.K.; writing—review and editing, V.K.; visualization, N.C.-P., D.A., M.P. and P.N.; supervision, M.P.; project administration, D.A., N.C.-P. and M.P.; funding acquisition, D.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research has been published with the support of Latvian Council of Science (Latvia), a research project "Quadruple Helix Concept (QHC) as base of the next generation PPP model" (no. lzp-2020/1-0062).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** Data available upon request.

**Acknowledgments:** The authors are grateful for the long-term cooperation with the Baltic University Program and the initiative to study the situation in the Member States in depth.

**Conflicts of Interest:** The authors declare no conflict of interest.
