The emotional make-up of a creature can be seen as a complex melody. The melodies of all living things together is a grand symphony of all emotions, this is called the Heartsong.

Those who pratice the art of spellsinging can use the Heartsong to influence other creatures' emotions. Make them angry, or scared, make them friendly or hostile. Any emotion can be inspired onto others by a skiled spellsinger. Spellsinging is a misnomer, because everything that can be done by voice can also be done by using instruments. Storytellers and poets can also be spellsingers, even though they do not sing.

NWN specifics Spellsinging is not mechanically implemented in NWN. Characters can be granted spellsinging abilities through CDQ/WLDQ for example. These characters can then have items or special abilities they can use. Usually, these characters have levels in the Bard class.