OPENCities is a project initiated by British Council Spain, to help cities to become more open and competitive. OPENCities demonstrates how international populations contribute to cities long term economic success and advocates for openness as a way forward for cities willing to play an international role. It has developed a tool to benchmark and analyse openness (the OPENCities Monitor). Overall, the project's goal is to highlight the importance of openness for cities' international success and competitiveness. Purpose Worldwide people are migrating to cities and by 2050 two thirds of the world population will live in urban areas, and as of 2014, 54% already do. This growing urbanisation, together with the commercial and economic globalisation results in increasingly diverse population. The importance of human capital and human creativity as one of the key location factors explaining sustainable economic long-term growth is significant and rising, with urban regions competing globally to attract the highly qualified and talented labour. Cities must therefore be attractive and open. They must provide a tolerant environment for talents and technology (Richard Florida) to attract and retain these international population groups. OPENCities identifies the link between international migration and economic growth, measures the multidimensional phenomenon of openness and provides qualitative recommendations towards internationalisation, integration and diversity policies on local level. Definition of openness In the context of the OPENCities project, openness is defined as “the capacity of a city to attract international populations and to enable them to contribute to the future success of the city”. As openness is a multi-dimensional phenomenon it can be hardly measured. During the OPENCities Monitor feasibility study conducted by BAK Economics, 54 indicators were identified to measure openness towards international populations in quantitative as well as qualitative terms. These indicators were mainly chosen due to their international availability and comparability on city or regional level. These indicators capture inputs and overall conditions as well as outputs or outcomes. They also take into account the perception of international migration groups regarding immigration policy or the value of ethnic diversity. Later on, they are aggregated into 11 areas with different weightings, namely: Migration Freedom Barriers of entry Quality of Living International presence Education International flows Infrastructure International events Standard of living Diversity actions The different weightings of the indicator results are based on a survey conducted by BAK Economics among 140 respondents in 16 cities. The weights were apportioned due to the relative importance