Backed by the East of England Development Agency, the proposals for the vast site next to the river Ouse will combine residential development with leisure and retail uses.
The practice - which is currently drawing up plans for Najaf in Iraq ( British office to redesign Iraqi city) - had already worked on the King's Lynn Urban Development strategy before being officially chosen to create a masterplan for the marina.
It was during these preliminary studies that LDY recognised the urgent need to develop the town's waterfront as part of a wider regeneration plan for King's Lynn.
The proposed marina, which would link into the inland waterways network as well as providing berths for sea-going craft, is expected to win the backing of the Borough Council of King's Lynn and West Norfolk shortly.
Councillor Nick Daubney, deputy leader of King's Lynn and West Norfolk borough council said: 'The proposals for a marina in King's Lynn present an exciting opportunity for the town and the commissioning of consultants to undertake the masterplan is a major step towards the achievement of this.'
The LDY masterplan - which will suggest a number of different design approaches - is due to be unveiled this autumn.
The proposals will then be put out for consultation.