• Air Waybill (AWB): This is the document of title to the goods travelling by air and is therefore non-negotiable. It travels with the cargo and acts as evidence of delivery of the goods travelling on board the plane.
• Commercial invoice: Document establishing the conditions of sale for the goods and their specifications. Serves as proof of sale.
• Packing list: A list of the contents in a package, completing the information of the invoice, which must be issued by the sender.
• Customs clearance authorisation: Document with which an importer or exporter authorises a customs agent to submit one or several customs declarations on their behalf.

• Delayed shipment: The most common causes of delay are inefficient management of port times and formalities. Other variables may also affect the shipment, such as circumstances of force majeure, like a storm for instance, or, in some parts of the world, the risk of a pirate attack.
• Lost goods: While this represents a very low risk today, it can occur in the event of problems such as the boat sinking or breaking down, as well as due to robbery or theft in ports of loading and destination in countries with high levels of corruption.
• Moisture, humidity or extreme temperatures:Environmental conditions must be perfectly controlled to prevent the cargo from being rendered unusable due to moisture, humidity or extreme heat or cold. All cargo must therefore be transported in containers suited to their particular characteristics and checked to ensure that they are properly closed. They must also be correctly loaded, unloaded and stored.
• Contamination: Interaction between different goods can ruin them. The goods must therefore be well packaged and properly stowed in the hold to prevent their contamination.
• Natural disasters: Natural disasters are becoming more frequent and serious in recent years; this represents the most unpredictable risk on the list.
• Computer threats: This is one of the new risks of international maritime transport since the famous NotPeya attack suffered by Maersk. Companies and ports are therefore currently working on logistics cybersecurity.

We can distinguish between different kinds of ships for maritime transport, depending on the load they transport:

• • General freighters:These are basic cargo ships; they can carry freight, but have no space for containers.
  • Container ships: Ships specially designed to carry goods in containers. They monopolize the majority of international dry freight transport and represent more than a half of all maritime trade.
  • Bulk carriers: The vessels best suited to transporting solid bulk cargoes.
  • Oil/gas tankers: Special tankers for transporting crude oil and by-products differentiated by their superior technical characteristics; all of them guarantee water tightness and structural resistance. Gas tankers have more sophisticated technology for storing liquefied gas and are divided into carriers of GNL and GLP, given that each one needs to be kept at a different pressure and temperature.
  • Reefer ships: Transport perishable food and commodities which must generally be preserved at very low temperatures
  • Ro-Ro ships: Have ramps and platforms for transporting vehicles with wheels, from private cars to industrial vehicles and loaded trucks. There are also hybrid versions of these ships which combine vehicle and passengers transport (ferries) and others that transport vehicles carrying containers (Ro-Lo)

A forwarding agent or forwarder is an agent who acts on behalf of importers and exporters to organise safe and economical goods transport. Among their many tasks, the most common are facilitating transport, selecting the most efficient route, taking out insurance policies, choosing the appropriate packaging depending on the cargo and taking care of its storage and/or distribution.