This is where you can apply filters and preferences to be more specific in your shopping/reshopping requests. As of today you can shop for:

Private Leisure Fare Products
Spanish Resident and Large Family Discounts
Filter only direct flights, or limit the number of stops enroute.
Specify the preferred Cabin
Pricing Option - This will return all the available flight combinations with the cheapest available fare. The results of this can be used to display a scheduled driven request. For example you could filter all outbound flights to only display those that arrive before a certain time, and also filter all the return flights to only display those that depart after a certain. This is useful for business travelers who need to arrive in time for a meeting and leave one the meeting has finished. An OfferPrice can subsequently be done for the preferred flights, with an upsell option, to then see all the fares available on the said flights.

NAME	DESCRIPTION	FORMAT	ALLOWED/POSSIBLE VALUES	NDC SERVICES
<Preference> If the Preference tag is included in the request, one or more of the following must be included. If more that one is used, then they must be sent in the same order as listed below.
FarePreferences / Types / Type Attribute PreferencesContext	Type of product selected.	Alphanumeric	For the Products currently available through our NDC channel, and the codes required to request them please see the information in Private Leisure Fares.	AirShoppingRQ OfferPriceRQ OrderReshopRQ
FarePreferences / TicketDesigs / TicketDesig	Spanish Resident discount code.	Alphanumeric	RC (Residente Canarias) BP (Residente Baleares) RM (Residente Melilla) RE (Residente Ceuta) BI (Para el interior de Baleares) DC (Para el interior de Canarias)	AirShoppingRQ OfferPriceRQ
FarePreferences / TicketDesigs / TicketDesig	Spanish Large Family discount code	Alphanumeric	F1 (General discount) F2 (Special discount)	AirShoppingRQ OfferPriceRQ
FlightPreferences / Characteristic / DirectPreferences	Maximum number of stops.	Numeric	0 or Empty - Direct Flights (Default) n (1, 2, 3...) - Maximum number	AirShoppingRQ OfferPriceRQ OrderReshopRQ
CabinPreferences / CabinType / Code	IATA PADIS Cabin code (This info will be applied as a preference, so other offers will also be returned).	1 Numeric	PADIS → 9873 Cabin class of service, coded 1 → First class, Highest class of service (First Class Category) 2 → Second class, Medium class of service (Business Class Category) 3 → Third class, lowest class of service (all economy/coach class categories) 4 → Economy/coach premium 5 → Economy/coach	AirShoppingRQ OfferPriceRQ OrderReshopRQ
PricingMethodPreference / BestPricingOption	To obtain all available flight combinations with the cheapest available fare. The results can be used to display a scheduled driven request. Only for unpaid Orders when used in OrderReshopRQ	1 Alphabetical	C (cheapest fares) Y (cheapest fares for a specific cabin type)	AirShoppingRQ OfferPriceRQ OrderReshopRQ

Preference examples

<Preference>
	<FarePreferences>
		<Types>
			<Type PreferencesContext="SPORT">758</Type>
		</Types>
	</FarePreferences>
	<FlightPreferences>
		<Characteristic>
			<DirectPreferences>5</DirectPreferences>
		</Characteristic>
	</FlightPreferences>
</Preference>

<Preference>
  <FarePreferences>
      <TicketDesigs>
        <TicketDesig>RC</TicketDesig>
      </TicketDesigs>
  </FarePreferences>
  <PricingMethodPreference>
      <BestPricingOption>Y</BestPricingOption>
  </PricingMethodPreference>
  <CabinPreferences>
      <CabinType>
        <Code>2</Code>
      </CabinType>
  </CabinPreferences>
</Preference>

<Preference>
	<FarePreferences>
		<Types>
			<Type PreferencesContext="SPORT">758</Type>
		</Types>
	</FarePreferences>
	<FlightPreferences>
		<...>
</Preference>