Macro to update only new values

[LouiseH24]

Hi,

I want to write a macro that uses one spreadsheet to update another.

I have a list of values in one spreadsheet (spreadsheet A) that I want to copy into another spreadsheet (spreadsheet B) when they have a value of 1 in column T (but not those with a value of 0). I then only want those that dont already exist in spreadsheet B to be pasted in the spreadsheet.

I would ideally like to run this macro off of a button.

Thanks

Lou

[DGagnon]

could you please provide a sample sheet to work with?