In a decision strategy, to use a customer property in an expression, you need to define Customer page in Pages & Classes and specify its class as Data-Customer. This allows you to access customer properties by using dot notation, such as Customer.Age or Customer.Gender. You do not need to define the property as a strategy property, use it without any prefix, or prefix it with the keyword Customer. Verified References: [Certified Pega Decisioning Consultant | Pega Academy], Decision strategies