>I know there is a way to display what the final value of @sSQL, but can't remember it. Can someone tell me how, please? Also, if you can spot what my syntax error is that would be great too!
>
>
>Frank, I can't immediately spot the syntax error - however, if you also place a SELECT @sSql at the end of the proc, the procedure will return the string...so you could use that in testing to bring back the value of @sSQL, and perhaps help in your debugging.

Thanks Kevin,

as I posted it I remembered the PRINT command so I added PRINT @sSQL and this came out:

SELECT [CommissionPK], 
					[CommissionsPaid].[Amount],
					[ChequeNumber],
					[ChequeDate],
					[ReceiptNumber],
					[ReceiptDate], 
					[ReceiptPK],
					[AgentNumber],
					[FirstName],
					[MiddleName],
					[LastName],
					[AgentPK]
				FROM CommissionsPaid 
					inner join ReceiptDetails on ReceiptDetailFK = ReceiptDetailPK 
					inner join Receipts on ReceiptFK = ReceiptPK
					inner join Agents on AgentFK = AgentPK
					LEFT OUTER JOIN Cheques ON [ChequeFK] = [ChequePK] 
WHERE 1 = 1
   AND ([LastName] LIKE @AgentName
   AND [ChequeNumber] IS NOT NULL
Msg 102, Level 15, State 1, Line 24
Incorrect syntax near 'NULL'.

Can you see anything wrong with that?