TSQL - Generating New Column With The Maximum Value Of Other Column

Hi guys,
In the query below, I need to insert a new Column that shows the last Document date.
In example,
Document Date Last Date
2006/01/15 2007/11/30
2007/03/25 2007/11/30
2007/11/30 2007/11/30
I need to show the last (max) date for each row.
Thanks in advance for any help,
Aldo.




Code Block
SELECT
Stock.VALUEDATE AS 'Document Date'

FROM
Stock As Stock
INNER JOIN ACCOUNTS AS Accounts
LEFT OUTER JOIN ACCSORTNAMES AS AccSortNames ON Accounts.SORTGROUP = AccSortNames.ACCSORTCODE
LEFT OUTER JOIN EXTRANOTES AS ExtraNotes01 ON Accounts.ACCOUNTKEY = ExtraNotes01.KEF AND ExtraNotes01.NOTEID IN ('17')
LEFT OUTER JOIN EXTRANOTES AS ExtraNotes02 ON Accounts.ACCOUNTKEY = ExtraNotes02.KEF AND ExtraNotes02.NOTEID IN ('18') ON Stock.ACCOUNTKEY = Accounts.ACCOUNTKEY
INNER JOIN DOCUMENTSDEF AS DocumentsDef ON Stock.DOCUMENTID = DocumentsDef.DOCUMENTID

WHERE
Accounts.SORTGROUP Between '0' AND '379' AND
Accounts.SORTGROUP Not Between '100' AND '150'
AND Stock.DOCUMENTID In ('1', '4', '5', '11', '78', '95')
AND Stock.STATUS Not In ('0', '2')
AND Accounts.SORTGROUP Between '0' AND '379'
AND Accounts.ACCOUNTKEY Like '313%'