A Backup Reinforcer is a type of reinforcement strategy commonly used in behavior modification and conditioning. This technique involves providing an alternative or secondary reinforcer when the primary reinforcer is not readily available or deemed inappropriate for a particular situation.

The backup reinforcer acts as a substitute for the primary reinforcer, maintaining the reinforcement value and reinforcing the desired behavior. It is typically selected based on its effectiveness in motivating the individual, even though it may not have the same inherent value or desirability as the primary reinforcer.

By using a backup reinforcer, behavior modification programs can ensure consistent reinforcement, even in situations where the primary reinforcer is unavailable. This method helps to maintain and reinforce the desired behavior, maximizing the effectiveness of the conditioning program.