USE [DB1]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[TableA](
	[Id] [tinyint] IDENTITY(1,1) NOT NULL,
	[Area] [nvarchar](10) NULL,
	[Item] [nvarchar](10) NOT NULL,
	[Description] [nvarchar](50) NOT NULL,
 CONSTRAINT [PK_TableA] PRIMARY KEY CLUSTERED 
(
	[Id] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON, FILLFACTOR = 85) ON [PRIMARY]
) ON [PRIMARY]
;

INSERT INTO dbo.TableA
(
Area, Item, [Description]
)
VALUES('A1', 'B1232', 'Thingymebobs')
;

INSERT INTO dbo.TableA
(
Area, Item, [Description]
)
VALUES('A4', 'B4352', 'Whatits')
;

INSERT INTO dbo.TableA
(
Area, Item, [Description]
)
VALUES(Null, 'B8769', 'Dunno')
;

USE [DB1]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[TableB](
	[ColId] [nvarchar](10) NOT NULL,
	[DeliveryName] [nvarchar](60) NOT NULL,
 CONSTRAINT [PK_TableB] PRIMARY KEY CLUSTERED 
(
	[ColId] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON, FILLFACTOR = 85) ON [PRIMARY]
) ON [PRIMARY]
;

INSERT INTO dbo.TableB
(
ColId, DeliveryName
)
VALUES('A1', 'Acme1')
;

INSERT INTO dbo.TableB
(
ColId, DeliveryName
)
VALUES('A4', 'Acme4')
;

INSERT INTO dbo.TableB
(
ColId, DeliveryName
)
VALUES('A8', 'Acme8')
;

INSERT INTO dbo.TableB
(
ColId, DeliveryName
)
VALUES('A9', 'Acme9')
;

SELECT b.DeliveryName, a.Item, a.[Description]
FROM 
TableA a JOIN Tableb b ON --????
;

SELECT b.DeliveryName, a.Item, a.[Description]
FROM 
TableA a JOIN Tableb b ON (a.Area = b.ColId) or (a.Area is null)

SELECT b.*, a.*, x.* 
FROM TableB b
LEFT JOIN TableA a ON b.ColId = a.Area
LEFT JOIN TableA x ON x.Area IS NULL AND a.Area IS NULL