This SSATP publication, jointly prepared with the World Bank, provides best practice guidelines for mainstreaming road safety in regional road trade corridors (RTRCs) investment programs in low and middle income countries (LMICs). The benefits of both physical and institutional improvements implemented under trade and transport corridor investment projects in developing countries have been often compromised by the increases in road accident risks as a result of increased truck traffic volumes and higher speeds. Therefore, there is a clear need to maximize the effectiveness of these investments in RTRCs through more comprehensive and efficient interventions in road safety; however, the available guidance on how corridor projects should address road safety issues has been found to be limited. These guidelines intend to fill this gap and provide a tailored approach to RTRC road safety priorities by (i) highlighting global best practice road safety management in regional trade corridors; (ii) summarizing current road safety management capacity in RTRCs in LMICs; (iii) outlining generic components of best practice road safety investment projects; and (iv) setting out a roadmap and a range of tools to assist the identification, preparation and implementation of road safety projects in RTRCs.