Create a block of components for PCB placement and routing reuse

I know this has been asked for previous versions of Allegro. But can anyone suggest the flow methods for design block reuse please.

The blocks would be in both schematic Design Entry and Allegro 16.6-2015.

Is it easy to create a pre-defined/pre-routed Schematic and PCB block that could be dropped into several designs. Would the Design Entry use a hierarchical design element? How would the Design Entry block relate to the Allegro PCB block?