if updated(field1)
	if field1 = 1
		if field2 = 1 
			begin
				update mytable set field2=0 where mytable.id = (select id from inserted)
				exec SP_WriteBillingRecord (select ID from inserted)
			end

			exec SP_WriteBillingRecord (select ID from inserted)
		end
	else
		exec SP_WriteBillingRecord (select ID from inserted)
end

SELECT ...
FROM inserted AS I
     LEFT OUTER JOIN deleted AS D
         ON D.MyPK = I.MyPK
WHERE (I.MyCol <> D.MyCol OR (I.MyCol IS NULL AND D.MyCol IS NOT NULL) OR (I.MyCol IS NOT NULL AND D.MyCol IS NULL))

alter TRIGGER TrgTest
   ON  client 
   AFTER UPDATE
AS 
BEGIN
	SET NOCOUNT ON;
	-- Create temporary Table of updated positive and negative responders 
	select 
		i.client_id,
		d.positive_responder as Dpositive_Responder,
		d.negative_responder as Dnegative_Responder,
		i.positive_responder as Ipositive_Responder,
		i.negative_responder as Inegative_Responder
	into #tmpResponders
	from inserted as I 
	left outer join deleted as d on d.client_id = i.client_id
	where ((i.positive_responder <> d.positive_responder) or
			(d.negative_responder <> d.negative_responder))
	-- Declare Variables
	declare @dPos bit,
			@dNeg bit,
			@iPos bit,
			@iNeg bit,
			@NextRowId int,
			@CurrentRowId int,
			@LoopControl int
	-- Initialize Variables
	select @LoopControl =1
	select @nextRowId = min(client_id) from #TmpResponders 
	-- Make sure we have some data to work with 
	if isnull(@nextRowId,0)=0
		begin
			--select 'No data found to work with'
			return
		end
	-- Get the first row 
	select @CurrentRowId = Client_id,
			@dPos = Dpositive_Responder,
			@dNeg = Dnegative_Responder ,
			@iPos = Ipositive_Responder,
			@iNeg = Inegative_Responder
	from #TmpResponders
	where client_id = @NextRowId
	-- Start the main processing Loop 
	while @LoopControl = 1
		begin 
			--------------------------------
			-- Do Row by row processing here
			--------------------------------
			print @CurrentRowId
			--------------------------------
			--------------------------------
			--------------------------------
			-- Reset Looping variables
			select @NextRowId = null 
			-- Get the next Client_ID
			select @NextRowId = min(client_id)
			from #TmpResponders
			where Client_Id > @CurrentRowID
			-- Check we have a next rowID
			if isnull(@NextRowId,0) = 0 
				begin 
					Break -- Stop processing the loop
				end
			-- Get the next row 
			select @CurrentRowId = Client_id,
				@dPos = Dpositive_Responder,
				@dNeg = Dnegative_Responder ,
				@iPos = Ipositive_Responder,
				@iNeg = Inegative_Responder
			from #TmpResponders
			where client_id = @NextRowId
		end -- Loop End
END
GO