This is the Final Report of the ETI project by Delta Energy & Environment to Review International Smart Systems and Heat Initiatives. This follows an initial piece of research undertaken by the ETI in 2011 examining this question.The work is intended to provide a digestible overview which links to the driving policies where appropriate, and complements a review undertaken during the scoping phase of the programme.The report:Examines initiatives (with a clear focus on heat), successes and lessons learned;Their outcomes / next steps; and possible learnings for the UKIdentifies the policies driving these initiativesIdentifies who’s involved and whyKey recommendations:Recommended countries where there are many learnings for the ETI are Denmark and the Netherlands– heat pumps, market structures, district heating, and exploiting synergies between electric and gas networks.Specific projects / areas for investigation in these countries are pointed outConsider customer recruitment for trials at a very early stage and place the customer proposition at the heart of project designThe ETI may be able to utilise platforms / hardware / software that has already been developed for other projectsWe see an absence, generally, of how gas, electricity and heat networks can work together, but some projects integrating two networks into a wider system. We believe this is a critically important aspect of a ‘smart heat system’Business models and market frameworks that the ETI could utiliseExamples of highly relevant purely private sector innovations