>Getting "Incorrect syntax near the keyword 'AS'."
>
>

>CASE WHEN OL.OL_STATUS >= 3 THEN 0 ELSE
>	CASE WHEN OL.OL_TERM_DATE < > '1901-01-01' AND GETDATE() > OL.OL_TERM_DATE THEN 0 ELSE
>		CASE WHEN b.BookedQty IS NULL THEN OL.OL_NEGOT_QTY ELSE
>			CASE WHEN b.BookedQty > OL.OL_NEGOT_QTY THEN 0 ELSE OL.OL_NEGOT_QTY - b.BookedQty END AS [Remaining Blanket Qty],
>

>
>Thanks

You should have as many ENDs as CASEs you open.
That is why always try to use one case (if it is possible of course).
Remember CASE statement has two syntaxes:
1. CASE WHEN ....
2. CASE SomeField WHEN Value ...

CASE WHEN OL.OL_STATUS >= 3
          THEN 0
     WHEN OL.OL_TERM_DATE < > '1901-01-01' AND GETDATE() > OL.OL_TERM_DATE 
          THEN 0 
     WHEN b.BookedQty IS NULL
          THEN OL.OL_NEGOT_QTY
     WHEN b.BookedQty > OL.OL_NEGOT_QTY 
          THEN 0 
     ELSE OL.OL_NEGOT_QTY - b.BookedQty
END AS [Remaining Blanket Qty],