Luxury boat producer Princess Yachts has secured £4.6m of government funding for a new boatyard in Plymouth.
The company said the money from the Regional Growth Fund (RGF) would secure 400 jobs in the city.
The French-owned firm said the RGF offer had persuaded it against the alternative of buying an overseas yard, possibly in Germany.
Plymouth-based Plessey Semiconductors is to build a new factory with £3.1m from the RGF, safeguarding 199 jobs.
Building order book
Business Secretary Vince Cable announced the grants later as part of a £30m round of RGF support for Devon companies.
Princess, which employs nearly 2,000 people in Plymouth, is spending £35m on the South Yard where it will make 100ft-plus boats.
Managing director Chris Gate said: "We were looking at a number of options. The local favourite was Plymouth, but it was up against competitive overseas alternatives.
"The favourite alternative was to buy a yard in Germany."
Work has already started on the infrastructure at the premises which Princess bought from the Ministry of Defence.
Mr Cable said: "Growing businesses like Princess Yachts and Plessey Semiconductors that are creating high tech, and highly skilled jobs are precisely the sort of companies that the government wants to support.
"Through the Regional Growth Fund, and more widely through our long term industrial strategy, government can give business the clarity and confidence to invest for the long term.
"That creates growth, and jobs for people here in the South West and all across the country."