Economic rent is profit beyond the normal profit. There are many types of economic rent, since rent may derive from different causes. While monopoly rent is caused by differences in market power, resource rent ha its reason from resource scarcity and market failure related to this. Such types of economic rent could be said to be caused by different types of market failures. Quasi rent is another type of economic rent which may occur in fisheries. Quasi rent is rent based on unpredictable and fluctuating markets and resource base, and the economic activity aiming to adjust for such fluctuations.