A purebred Arabian Horse is one which appears in any purebred

Arabian Stud Book or register listed by WAHO as acceptable

As of January 1, 1993, the following Stud Books are considered acceptable 

Algeria Lithuania
Argentina Morocco (includes Libya)
Australia Netherlands
Austria New Zealand
Bahrain Norway
Belgium Oman
Belize Poland
Brazil (includes Paraguay) Portugal
Canada Qatar
Chile Romania
Colombia Russia
Costa Rica Saudi Arabia
Czech Republic  Slovakia
Denmark  South Africa
Egypt (EAO & Supervised Studs) Spain
Finland Sweden
France Switzerland
Germany (includes Luxembourg) Syria
Hungary Tunisia
Iran United Arab Emirates
Iraq United Kingdom
Israel U.S.A. (includes Mexico)
Italy Uruguay
Jordan Venezuela
Kuwait Zimbabwe