From Project: Redcap
In the basic Fifth Edition rules, the Permanent Duration does not exist. there are two ways to get a permanent magical effect, and a third way to create long-lasting effects that approximate permanency.
First, just about any effect can be made permanent via an Enchanted Device. One way to do this is to make a "constant effect device" as explained in the sidebar on p. 99. For instance, to turn someone permanently into a frog, you could make an enchanted device that attaches to the victim, say a collar or cloak, with a constant effect. Then design the effect so it can only be activated or deactivated by you ("Effect Use", p. 99) and build in a Requisite so the item changes along with the wearer, becoming part of the animal form. Then, if you manage to get someone to put on the item (and it penetrates his Magic Resistance), poof! he's a frog, he cannot voluntarily change back, the item can't fall off, and the effect does not expire. Of course, you had to spend one or more seasons in the lab to make the item, which is a big investment just to turn one person into a frog. Also, the item would cause Warping as a continuous effect (p. 167).
The other way to get a permanent effect is with a Momentary Duration Creo Ritual as explained on p. 112. Some people are a bit confused by this, so here is re-phrased explanation. Normally a Momentary Duration spell happens and then is gone: if you conjure an apple with Momentary duration, an apple flickers into existence and then the spell wears off and it flickers back out. As a special exception, if you use a Ritual, then the apple would become real and non-magical during that moment, and it would act like a non-magical apple when the Momentary duration wore off. Non-magical apples keep existing, so the apple would be "permanent" and indeed it could not be dispelled.
The Ring Duration can create long-lasting effects with no pre-determined expiration date. If the ring is graven into a durable material such as stone or metal, the spell will last indefinitely until the contents of the Ring are moved.
Other Permanent Effects
The Mysteries: Revised Edition includes some new options for magi who've been Initiated into certain mysteries, including a way to create permanent effects.
The history of this page before August 6, 2010 is archived at Legacy:permanent_effects