"Close liaison" means to have a very strong and direct connection or collaboration with someone or a group. It implies working closely together and maintaining constant communication to achieve a common goal. Full definition
Developed and maintained close liaison with project client contacts, core team members and Project Managers. (jobhero.com)
Second, it suggests that closer liaison between criminal justice and mental health might prevent violence in high - risk individuals.» (sciencedaily.com)
incorporate local stories, involve local young people, and continue close liaison with the local Indigenous communities (beyondblue.org.au)