To Concentrate a magical discipline is to follow a particular path to the exclusion of all others. The primary benifit for concentration is that the cost for learning and/or raising any related ratings in that magical discipline are halved. The downside to concentration is that all other types of magic are forbidden to the character, including any magicks that they might have already learned from an opposing discipline (the ability is lost).

• Concentrating Common ("innate") Magic means:
  • The character can only gain or improve Talents.
  • Charms, Spells, and Feats are forbidden.
• Concentrating Theism means
  • The character can only gain or improve Affinities, and Feats.
  • Talents, Charms, and Spells are forbidden.
• Concentrating Animism means
  • The character can only gain or improve Charms or Fetishes.
  • Talents, Affinities, and Spells are forbidden.
• Concentrating Wizardry means
  • The character can only gain or improve Spells.
  • Talents, Affinities, and Charms are forbidden.

It costs One (1) HeroPoint to Concentrate one's magic during play, but it is a free option during character generation.

Other forms of concentration have been introduced in sourcebooks for Glorantha (such as concentration in a specific religion, et cetera), and it is also possible to "backslide" out of a Concentration, in order to gain abilities in another discipline.