This paper is one of five papers presenting research results from the Monitas Joint Industry Project (JIP). The name Monitas stands for Monitoring Advisory System. The project has developed the Monitas system that presents, explains and advises on the fatigue lifetime consumption of FPSO hulls. The advice is based on comparisons between the design and the actual fatigue lifetimes predicted by replacing the design factors like operational settings, environmental conditions and hydro-structural response by the measured data. This paper specifies how to implement the Monitas system for FPSO units in the most effective way. This includes interfaces with other systems like the unit monitoring system and the environmental monitoring system. Requirements with respect to hardware and sensors typical for the Monitas system are given. The specification is illustrated by examples from present applications of the Monitas system, i.e. on board the Glas Dowr FPSO unit and the Usan FPSO unit.