David try this

HTH Mike

IF Object_ID('TempDB..#Parent')>0

 DROP TABLE #Parent

IF Object_ID('TempDB..#Child') > 0

 DROP TABLE #Child

CREATE TABLE #Parent

(

 Pk int,

 OtherStuff VarChar(20)

)

CREATE TABLE #Child

(

 FKParent int

)

DECLARE @Count int

Set @Count = 0

While @Count <10

Begin

Set @Count = @Count + 1 

 INSERT INTO #Parent(PK)

  VALUES(@Count)

 IF @Count < 5

 INSERT INTO #Child(FKParent) VALUES(@Count)

End

GO

SELECT P1.pK

FROM #Parent p1

WHERE NOT EXISTS

 (

  SELECT p.pk

  FROM

   #Child c

  JOIN

   #Parent p

  ON c.FKParent = P1.pk

 &nbsp

--

/*

Results 5,6,7,8,9,10

Records 1-4 have parents

Edited to change Mark to David. Addressed the wrong person sorry 

*/