Procedures sometimes stipulate that a transaction must be confirmed by two persons at all times. This is how bank vaults are accessed, or ATM devices are installed. The reason is usually to make it uninteresting for any single person to abuse a position of power.

The Sesame system is designed with this possibility in mind. A single-card setup usually restricts transactions by demanding one confirmation, but it is just as well possible to restrict transactions by demanding more than one confirmation code. Such codes would have to come from different Sesame cards.

When you register an additional Sesame card under an account, you are asked why you are adding a card. Purposes can be either to increase the level of backup or to increase the restrictions on transacionts. To setup for an additional required Sesame confirmation code, you would choose the latter purpose.