Hi @duncant ,
Assuming that the lookup column name is "Lookup" and you're trying to read the lookup column value in a apply to each loop, here's how the expression would look,
items('Apply_to_each')?['Lookup/Id']
You can get the Lookup value or Id from the get items as well (in case you are getting items from a SharePoint list using the "Get Items" action), using the dynamic content popup,

Hope this helps 🙂
Kind Regards,
Shaik Sha
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