Description Like famous British explorer Captain James Cook and his vessel, the Endeavour, Endeavour International is looking to make new discoveries of great economic benefit. The exploration and production company has traditionally sought developed new oil assets by buying stakes in mature North Sea fields that the oil majors are moving away from. In a major strategic shift, Endeavour International is also developing a second core area, the US, and is buying stakes in oil and gas properties, particularly shale plays, in Louisiana, New Mexico, and Texas, and elsewhere. In 2010 Endeavour International reported proved reserves of 18.4 million barrels of oil equivalent, 30% of which were located in the UK.