Ted on Flex is previewing enhancements in the next version of Flex. First up is a look at better tools for designing/laying out your Flex app. I currently end up with a chain of HBox VBox components embedded together to get my layout ‘just’ right so the new advanced constraints sound great:

Advanced Constraints:
There are 2 new components for constraint based layout, mx:ConstraintRow and mx:ConstraintColumn. These new components allow you to subdivide a containers supporting absolute positioning. Where Flex 2 provided parent-child constraints, Advanced constraints allow definition of sibling relative constraints.