Rounds have been held roughly every
two years from first in 1964 to 18th in 1998. There is no pre-determined
or statutory interval between them. Before a Round is announced,
Government officials talk to companies to discuss areas of potential
prospectivity. Sometimes this process has taken form of a formal
'nominations stage'. Officials then consult with other Government
Departments and various NGOs who may also have an interest to establish
whether it is practicable to licence requested blocks.