DECLARE @Part1 TABLE
(DHBService varchar(10),
 PU varchar(10),
 Budget decimal(10,2),
 Admission varchar(10))

INSERT @Part1
SELECT 'ABC', 'M00', 200, 'Acute' UNION ALL
SELECT 'ADC', 'M10', 300, 'Severe'

DECLARE @Part2 TABLE
(DHBService varchar(10),
 PU varchar(10),
 Admission varchar(10),
 Actuals decimal(10,2))

INSERT @Part2
SELECT 'ABC', 'M10', 'Severe', 412.88 UNION ALL
SELECT 'ADD', 'M12', 'Acute', 333

SELECT coalesce(P1.DHBService, P2.DHBService) AS DHBService, 
	coalesce(P1.PU, P2.PU) AS PU,
	coalesce(P1.Admission, P2.Admission) AS Admission,
	P1.Budget, P2.Actuals
FROM @Part1 P1
FULL JOIN @Part2 P2 ON P1.DHBService = P2.DHBService AND P1.PU = P2.PU AND P1.Admission = P2.Admission