Risk reduction is one of the strategies of dealing with risks that consists in taking some measures to reduce the level of risk. In order to reduce a risk, we have to take some measures (Countermeasures) in order to reduce whatever causes the risk. In other words, we take an action that should reduce the impact or the probability of the risk to an acceptable level. The acceptable level is called a Residual Risk Level.
When should we try to reduce the risk?
Whenever it is possible and economically advantageous. This is the most common way of dealing with risks, as there is usually a way to do it.
What other possibilities do we have to deal with risks?
For example, we can transfer the risk to someone else, an insurance agency for instance, or we can share the risk with someone. We can also choose to totally avoid the risk by not realizing our intention at all, or we can decide that we are able to assume the potential consequences and simply accept the existence of the risk.