[joegrundman]

All units must be able to trace a line of supply to a supply source. The line can be any length and may go across the sea.

If the supply line is to an unlimited supply source (London, the US box, Berlin, Rome, Seoul, Tokyo are some of the unlimited supply sources) the the units are fully supplied. Bridgehead counters are also unlimited supply sources for the turn in which they are placed.

If the supply line is to a limited supply source (most minor country capitals, captured major power capitals, industrial centers) the units are under limited supply. This means that some operations are impaired.

- armor units fight as infantry (reduced speed, no Zoc, no exploit or overruns)
- minus 1 to the CTL
- air units may not conduct offensive operations
- naval units may not conduct offensive operations or escort sea supply or invasions
- no strategic bombing
some other factors.

Clearly it is much better to be fully suppllied. There is no limit to how many units may be supplied from a supply source.

If a unit cannot be supplied, then it is isolated. Isolated units cannot move, and fight at reduced strength. If isolated units have not reestablished supply by the end of the owning player's turn, they surrender.

Supply by sea

sea supply lines can be escorted, be given air cover, and be attacked by hostile air and naval units.