This paper discusses ship motions moored at a quay wall as the harbour calmness index. In this paper, we show instances of interruption and suspension of cargo
handling due to ship motions.
　The allowable ship motions were estimated in terms of the type and size of a ship through executing numerical simulations not only for each instance of interruption and suspension of cargo handling which might be caused due to ship motions but also for exeuction for cargo handling. These values were also evaluated and revised respecting opinions of cargo handling operators. Then the Allowable Ship Motions for cargo handling at wharves are proposed.