However, like David, the vouchers have proven to be more effective than expected. But it makes sense in terms of what we know about why people use drugs. Also, cocaine users reach a point where they want help. They are an alternative that is available immediately, but only if cocaine is not used. This is the heart of the theory that drives the treatment strategy.
Cocaine produces powerful reinforcing effects.
The voucher, on the other hand, is reinforcement for not taking cocaine. Although the dollar value of the voucher may not be great, the value of this alternative, immediate reinforcer can be quite high. Quite simply, reinforcement is a basic principle of human behavior. When we're discussing cocaine use, we're talking about behavior that is very sensitive to its consequences. Cocaine abuse is not guided by a moral compass or free will.