The company leading the decommissioning of Dounreay has awarded contracts totalling more than £12m to three firms for the next stage of the project.
NDSL, Nuvia and Morson International will supply 70 staff to dismantle plant and machinery in some of the most hazardous areas of the Caithness site.
They will wear special suits as protection against radiation.
Dounreay Site Restoration Limited (DSRL) said the contracts should help it save millions of pounds.
DSRL, which is leading the decommissioning process, said the contracts would run for four years and start in August.
NDSL has a team of engineers and industrial chemists and offices in Forss and Dornoch in the Highlands and Cumbria.
Cheshire-based civil engineering company Nuvia specialises in working in the nuclear industry, while recruitment firm Morson International is headquartered in Salford, Manchester.