VFP IIF() can be replaced with T-SQL CASE() function

>How do I do this in SQL?
>
>

>IIF(Trade.decTrade_Product_Balance <> 0 AND
>	(Trade.sTrade_Type_Pay_Rec = 'PAY' OR Trade.sTrade_Type_Pay_Rec AND Trade.sTran_Group_CD <> 'MAR'),
>		Transactions.decTrans_Amt, 0)
>