From 1998 to 2002 we monitored changes in the relative abundance of Asian houbara bustard Chlamydotis macqueenii across the greater part of its range in Kazakhstan. The areas most frequented by houbara bustard were the Kyzylkum region, with 35% of total sightings, and the Betpak-Dala/Muyunkum region with 25%. For all survey areas combined, mean relative abundance ranged from 0.004 to 0.017 individuals seen per km driven. Density estimates ranged from 0.025 to 0.086 houbara bustard per km2. Between 1999 and 2002 spring relative abundance and density decreased by 65 and 51% respectively. Likewise, autumn relative abundance decreased by 56% from 1998 to 2001 and density decreased by 35% between 1999 and 2001. Kyzylkum had the greatest declines in relative abundance during both spring (78%) and autumn (61%). It is highly probable that this observed decline in houbara bustard populations is linked to hunting and poaching pressure, both in Kazakhstan and on the wintering grounds of these Central Asian breeding populations.