The NetZeroCities project has analysed regional and national commitments included in Climate City Contracts and created a concise, actionable document with recommendations and best practices. This resource is designed to support Mission Cities seeking to strengthen their collaboration with regional and national authorities, helping to secure impactful commitments in future iterations of their Climate City Contracts. Additionally, the document serves as an inspiration for regional and national authorities, offering practical recommendations and ideas for endorsing or contributing meaningful commitments to support cities on their journey to climate neutrality.