The question has already been answered, but to help you understand how DSL expansion works, here's what happens. 1. The expander goes down the list and matches the first expression against all lines in your rules. So, rule dsl2drl_1 when Get month summer then Print months; end becomes rule dsl2drl_1 when $month: Month(); summer then Print months; end 2. The expander tries to match the second expression, and fails. 3. The expander tries to match the third expression, and succeeds, leaving you with the following DRL. rule dsl2drl_1 when $month: Month(); summer then System.out.println("Month: " + $month.getId());; end Looking at the LHS of the rule, this will not compile. Matt