[Mini1380]

You need to buy an approved Child seat. Look for ISOFIX for international standards or LATCH for USA standards. Some child seats can possibly be retrofitted with the LATCH system. The USA is suppossed to be have all cars fitted with the LATCH system on September 2002 and all child seats should be fitted with the system as well. I found a seat from K-MART that has the LATCH system.

LATCH = Lower Anchors and Tethers for Children