Dispensation involves the Pope
giving advance permission to commit a sin
Examples of a dispensation are the Pope granting an abortion or divorce, or, the most common, a priest getting married.
Currently Pope John Paul II hasn't granted any dispensations that I know of, but they can be anything.
Historically, people of wealth but more of power get them granted.
The fiasco over Henry VIII and divorce spawned the Church of England fiasco.
Another name for dispensation is indult