=SUMPRODUCT(COUNTIF(INDIRECT("'"&A2:A4&"'!D3"),"D" ))
where A2:A4 holds the names of each sheet to be used -- extend if needed
best wishes
--
Bernard V Liengme
Microsoft Excel MVP
http://people.stfx.ca/bliengme
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"Mrfish" wrote in message
...
I would like to do a 3d countif across multiple sheets. I simply want to
count the cells containing 'D's. Something like
=COUNTIF(Start:End!D43,"D")
would be ideal if it worked!

Unfortunately I see now that countif() doesn't work with a 3d reference. I
see some other answers here have used a =sumproduct(n(... function to get
round this, but didn't understand it.

Can anyone here help?