The BubblingEvent is raised and propagated across all the widget hierarchy in the parent direction, and it is concentrated in one unique event procedure, so very interesting things can be done quite efficiently. You can read the full explanation in the "6 Forms with multiple PanelLayouts" example in the RC5formsTutorial from http://www.vbrichclient.com/#/en/Demos/GUI/FormEngine.htm, but as a summary I put the Olaf's comment here:
```VB
'One can use "normal" VB-Events for all the Widgets and GUI-Elements too of course, but
'then (as always) at the cost of defining a WithEvents-Variable for your CommandButtons and stuff.
'The additional Bubbling-concept allows for easier-Event-Handling in a "centralized sink", especially when
'we talk about "whole Groups of Controls/Widgets" (so, Control-Arrays are not necessary anymore 
'for "Event-Grouping")
```
It's a very good feature of the vbRichClient's widgets architecture.