Getting Count(*) into a varibale

Experts,

here is my sample code and have tried multiple options and couldn't get it worked to assign the count(*)  to my variable so that I can use that value for later


Declare @@Total

SELECT @Total  = count(*) FROM (
SELECT  T1.ItemID
FROM MyDatabase..MyTable T1
INNER JOIN
INNER JOIN
INNER JOIN
...
WHERE
GROUP BY T1.ItemID
      HAVING  
)
 

Thanks in advance.