DEN offi cials suggested to their Ministers that for new fi elds a scheme of staged approval should be introduced. For fi elds already under development it had been agreed that plans would be approved for the lifetime of the fi eld, but offi cials felt that greater fl exibility was desirable for new ones in order to accommodate any requirement of depletion policy. It was argued that life of fi eld approval was not of great value because the operator could not really predict the behaviour of production at the outset, and in practice plans were subject to revision. DEN offi cials thus felt that there was a case for establishing review points over the life of the fi eld. It was suggested that initial approval might be for, say, two years, followed by a second stage covering the production plateau. This would be adjusted to conform to national depletion policy. The third phase would be aimed at the maximisation of economic recovery. There might be a need to have an overriding minimum profi le to safeguard the viability of the fi eld.