Port State Control activities must be co-ordinated internationally. Therefore most port States have signed regional Memorandum of Understanding, covering most of the earth′s navigable waters; they are:

• Europe and Northern Atlantic (Paris MOU);
• Asia and Pacific (Tokyo MOU);
• Latin America (Acuerdo de Viña del Mar);
• Caribbean (Caribbean MOU);
• Western- and Central Africa (Abuja MOU);
• Black Sea (Black Sea MOU);
• Mediterranean (Mediterranean MOU);
• Indian Ocean (Indian Ocean MOU) and
• Gulf Region (Riyadh MOU).

MOUs have defined principles for their inspections. Under the Paris MOU the following items related to ECIDS systems on board are inspected:

• documentation whether the IMO Performance Standard has been met;
• existence of written manuals if ECDIS system is the main navigation system;
• existence of certificates showing that the mariners have been trained in ECDIS (IMO ECDIS Model Course) and are familiar with the ECDIS system used on board;
• existence of latest up-dates and new editions of ENC;
• existence of correct usage bands for the upcoming entire voyage,
• existence of additional nautical publications which have been defined by national carriage requirements;
• agreements between sensor data and their presentation on ECDIS system;
• existence of adequate back-up systems and
• existence of an up-dated collection of paper charts when the ECDIS systems is used in RCDS mode.

The selection of paper charts is the responsibility of the Master. It is required that the voyage can be finished safely if the ECDIS system suffers a total system malfunction.

Paris MOU has recommended chart scales which was adopted by other MOU:

• planning 1:750 000 to 1:1 500 000;
• open sea navigation 1:100 000 to 1:500 000;
• making landfall, navigation in areas with dense traffic, fairway and harbour area better as 1:100 000.