This report is the output of thefinalize toolkit phase (phase three) for the projectsustainability toolkit for transport projects. The overallobjective, as defined in the terms of reference, is 'tomake development projects more sustainable by reducing therisk of failure of projects attaining their long-termdevelopment goals and enhance the prospects for theirsustained impact on development ensuring that there is localcommitment to longer-term buy-in'. The main deliverableof the project is a project sustainability toolkit, of whichthis report outlines the final version. This toolkit helpsto gauge the potential for the project to be sustainableinto the long-term and provide advice to help overcomecommon barriers to the successful development andimplementation of projects. The guidance covers the expectedopportunities and constraints related to sustainability. Thetoolkit is intended to reduce the risk of project failure interms of sustainable development and enable recipientcountry clients to incorporate core sustainabilityprinciples into transport projects at every stage of projectplanning, design and delivery. This will improve theprospects for longer-term sustainability and will enhancethe long-term impacts of development projects. Task TeamLeaders (TTL's) will benefit from additional evidencethat supports investments intended to consolidate long-termdevelopment, and borrowers will benefit from projects withimproved and demonstrable longer-term beneficial impact. Thetoolkit provides general advice for transport sectorinvestments and is not modally specific. Information on thesub-components of the key sustainability principles has notbeen included since it was considered that this did not addvalue or further understanding of the issues.