In December 2005 Odyssey began archaeological investigation of the site believed to be HMS "Sussex". The company adhered to the project plan submitted and accepted by the Sussex Archaeological Executive, a committee of archaeological consultants approved by the UK Government. As of 2009, Odyssey had completed Phase 1A (the non-disturbance survey) and a substantial portion of Phase 1B (trial excavation of the site believed to be HMS "Sussex") to the satisfaction of the UK Government. Odyssey was authorized by HMG to complete phase 1B of the project.