Depicting step-wise refinement and/or decomposition in UML

I have set of high-level, abstract business use cases. I want to break down these business cases into more detailed use cases. I would like to indicate in my model somehow that the use cases are a step-wise refinement or decomposition of the business use cases.

I would like to do similar step-wise break downs of other elements like action nodes activity diagrams.

Can anyone tell me how to indicate these refinement/decomposition relationships among my UML elements?

I have been looking and looking on this topic and am lost.

Many thanks in advance.

Detroit, Michigan, USA

It sounds like you’re making a hierarchal diagram. I’ve commonly seen these in state machine diagrams where there is another state machine diagram within a state in a parent state machine diagram.

For space and formatting, I’ve seen annotated states with its contents referenced on another page. That is, there would be an overview state machine on one page and then the following pages would contain the detailed state machine from the states in the overview.