Five classes of membership are available:
To become a member, please select a membership level below and proceed to pay with a credit card, or you may mail in your payment.
* Defined by the World Bank as of July 2016.
To mail payment, please send to: (new mailing address)
3021 Zodiac Ct
Loveland, CO 80537 USA
Payment of membership fee by credit card is open to members in most countries, but does require confirmation of card number through PayPal. Please follow the link from the member application form to the credit card payment system for further details.