There are two principal categories of service concession arrangements:
(a) In one, the operator receives a financial asset - an unconditional contractual right
to receive a specified or determinable amount of cash or another financial asset
from, or at the direction of, the grantor in return for constructing (or upgrading) the
infrastructure assets, and then operating and maintaining the asset for a specified
period of time. This category includes guarantees by the grantor to pay for any
shortfall between amounts received from users of the public service and specified
or determinable amounts.