At the start of your move phase the first thing you must do is declare which units will charge. Except in a few unusual circumstances explained later, you are never forced to charge. It is always your decision which units, if any, will charge the enemy. However, charging is the only way models are normally allowed to move into hand-to-hand combat. If you want to attack an enemy then you must charge him - you cannot simply move into hand-to-hand combat without declaring a charge.

To declare a charge indicate which unit is charging and nominate the enemy unit it is going to attack. For example, you might declare that your Bretonnian Knight unit is charging the enemy's Saurus Warrior unit.

A unit may only declare a charge if at least one model in the unit can see at least one enemy model in the opposing unit. It is not necessary for every model to be able to see an enemy - the whole unit is assumed to have the enemy in sight so long as one model can do so.

Troops can only charge up to a predetermined distance - their 'charge distance' as explained later. When you declare a charge you must do so without measuring the distance to the target, you must therefore rely on your estimate of the distance to ensure your troops can reach their target.

When deciding whether to charge you must also take into account any terrain that might slow you down as described later. Deciding whether to charge or not calls for good judgement of distances!