Mr Lannen early career was with Aberfoyle Ltd where he worked in both technical and operating rolls at Cleveland Tin, Ardlethan Tin and the Melbourne head office. His last project was to take the Hellyer base metal mine in Tasmania from feasibility to full production as the mine manager. In 1990, Mr. Lannen started Mancala Pty Ltd, a specialist mining contractor and mine engineering group and managed Mancala's operations for over 25 years. As a mine contractor, Mancala has successfully completed projects in both metalliferous and coal in Australia and offshore. Projects have included whole of mine contracts in open pit and underground as well as specialist contracts in the development and recovery of shafts. Several key projects involved mechanized mining of narrow vein deposits.