I have the following table...
MemberID ServDate 001 12-12-2015 001 12-13-2015 001 12-15-2015 002 11-30-2015 002 12-04-2015
SELECT MemberID, ServDate, MAX(ServDate) OVER (PARTITION BY MemberID) AS LastServDate FROM Table
Standard SQL, so works in most modern RDBMS (including SQL Server and Oracle).
EDIT by the way, if you want to learn more: MSDN ref. for OVER