Lachlan Harcourt is to leave Willis to become National Client Development Leader at Marsh.

He has worked with Willis since 2001, most recently as MD of risk solutions.

For Marsh he will be based in Melbourne, reporting to Executive Director George Tarabaras.

Mr Harcourt will work in tandem with Sydney-based equivalent Ron Tomsic, who joins from Aon Risk Solutions next month.

The pair will share national responsibilities for business development, client retention and client development.