The Passenger Terminal Complex at Kuala Lumpur International Airport presently consists of a large Terminal 1, its Contact Pier& its Satellite A (20 km from the main terminal),  and the Low-Cost Carrier Terminal:
Terminal 1, the Main Terminal, has a Concourse (or ‘Contact Pier’) with A & B gates for domestic flights and G & H gates for international flights. Satellite A and the Low-Cost Carrier Terminal each have their own immigration facilities. The Aerotrain, a driverless train on an elevated rail, running every 3 minutes, connects presently the Main Terminal 1 & its Satellite A (& taking 3 minutes), and will also (upon its completion in 2012) serve the new Low-Cost terminal.

Terminal 1 - the Main Terminal, is situated between two runways, has five levels, two of which are undergound, Level 3 is the Arrivals Level, Level 4 is the Mezzanine Level, and Level 5 is the Departure Level. Its Concourse, or ‘Contact Pier’, connected to the Main Terminal, handles domestic flights of Malaysia Airlines, as well as some international flights. It also connects to the Satellite Terminal via Aerotrain at its center, and leads on Level 3 at left to domestic gates B2-B11, and at right to gates A2-A11. Level 4 leads at  left to international gates H2 to H11, at at right to the transfer counter and gates G2 to G11.

Level 1 leads to/from KLIA Express Train Station and Bus Station; it has a convenience store and a deli,
Level 2 has access to Parking C & D and Parking A & B on each side and to the PanPacific Hotel via 'buggy' service.
Level 3 is for both domestic & international arrivals, with customs clearance and baggage check A through M (no I), Immigration, and services and amenities (3 ATM machines, 2 money changers, 2 Surau prayer areas; the Pusrawi Medical Center).
Level 4, the Mezzanine Level, has access to airline offices and Food Paradise.
Level 5, the Departure Level, has an Information counter, 216 check-in counters at six separate islands and identified by letters AB, CD, EF, GH, JK & LM. The check-in services are for all arriving, departing or transitioning passengers.  A large number of integrated self-check-in kiosks (CUSS) are now available. 
Aside from a host of restaurants, cafes and fast-food establishments, as well as duty-free and regular shops, this terminal offers a Post office, CIMB Bank, 4 ATM machines, 2 foreign exchange counters, left luggage, unaccompanied luggage, and a Surau prayer area between the domestic and the inernational departure areas.

The Contact Pier of Terminal 1 - serving as domestic & international terminal - is connected to the Main Terminal, has levels 3 & 4. It also connects to the Satellite Terminal via Aerotrain at its center, and leads to the following gate areas:
(a) on Level 3 at left to domestic gates B2-B11, and at right to gates A2-A11, with immigration and transfer counter in the center. Level 3 houses a few shops and food establishments, the MAS Golden Lounge for domestic passengers, an ATM machine, currency exchange and a Surau prayer area.
(b)on Level 4 at  left to international gates H2 to H11, at at right to the transfer counter and Gates G2 to G11. Level 4 houses a duty-free shopping mall, Karyaneka, Kids Smrt Tunnel, fast-food and coffee shop. Close to the Aerotrain station, to the left, is a Surau prayer area, and an Information desk.

Satellite Building of KLIA - located on the opposite side Main Terminal's apron, near the air cargo area - and quite a distance from the Main Terminal - handles mainly international departing & arriving flights. It has a mezzanine and a passenger level  - both of which are cross-shaped, with a landscape area in the center.
The mezzanine level of the Satellite offers food & drink, and airline lounges.
The passenger level of the Satelite has airline gates divided into 4 zones: The West Zone with Gates C1-C6 houses the Aerotrain stop which connects to Terminal 1's contact pier. The north Zone has moving walkways and gates C11-C17; the East Zone has gates C21-C27; the South Zone has gates C31-C37.

Satellite A offers an abundance of duty-free and brand-name shops, fast-food establishments, free wireless internet access, Information desk, CIMB Bank, left luggage, Airside Transit Hotel, post office, nationwide express,  3R Reflexology & massage services, children's play areas, movie lounge and broadcasting movie, as well as sports channels. The transfer desk is near the landscape area in the center.
Lounges at the Satellite: Cathay Pacifc, China Airlines, Emirates, Singapore Airlines & Thai Airways, and the Plaza Premium Lounge.

3. The present Low-Cost Carrier Terminal (LCCT) does not have a transfer facility to the main terminal, offers less amenities, and has no airbridges. LCCT gates are marked P for domestic and T for international departures. Passengers needing to make transfers to another flight have to clear immigration, collect their luggage, clear customs, make their way to the main terminal and re-check-in with their connecting airline. To get to the Main Terminal, you need to take the Airport Liner bus, a 30-minute drive. NOTE: LCCT is a temporary terminal - a new KLIA2 low-cost terminal will replace the present LCCT as of April 2012 and will then be served by the Aerotrain.  No reference has yet been found regarding the prores of the new KLIA2 terminal.

City checkin and baggage checkout services - Kuala Lumpur City Air Terminal is a virtual extension of KLIA and provides for city check-in services at check-in desks and CUSS automats; and Rail Link Sdn Bhd offers baggage check-out services, where passengers only collect their baggage and declare taxable items.
 

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