Prestige classes offer an expanded form of multiclassing. Unlike the base classes, characters must meet requirements before they can take their first level of a prestige class. The rules for level advancement apply to this system, meaning the first step of advancement is always choosing a class. If a character does not meet the requirements for a prestige class before that first step, that character cannot take the first level of that prestige class. Taking a prestige class does not incur the experience point penalties normally associated with multiclassing.