I am trying to define a dynamic range on sheet 3, which I want to be
able to use as a dropdown list as a part of the data validation "list"
option.

But whenever I select the drop down list after creating the validation
rule (via data > validation), I cannot see my list.

Perhaps I am using the wrong formula for the dynamic range?

Here is what I am doing.

List is in Sheet 3, rows 1-10 (and growing).

Defined name is: =OFFSET('Sheet3!A1,0,0,COUNTA('Sheet3!!$A:$A))

In sheet 1, column C, I am selecting the column, then selecting data,
validation, list (and placing "=nameofmylist" in the source box.

Thanks for any thoughts......