There's no good way to do so. DL's are not a robust or reliable way to group
contacts.
You can nest a DL within another if you want to keep using them.

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Russ Valentine
[MVP-Outlook]
>I have several disrtibution list that I use to keep different teams up to
> date. The project I'm working on has ended but a new one is kicking off.
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>
> Thank you