One way to do what you want to do is to use the RANK function and make the query into a subquery as shown below:SELECT * FROM
(
SELECT Score_PlayerID,
YEAR(Game_Date) AS yr,
MONTH(Game_Date) AS mnth,
HighScore,
RANK() OVER (PARTITION BY YEAR(Game_Date),MONTH(Game_Date) ORDER BY HighScore DESC)
AS RN
FROM utScores
INNER JOIN utGames
ON Game_ID = Score_GameID
) s WHERE RN = 1;