Russian and foreign citizens and parties with no particular citizenship may become members of ISDEF, providing the individual is over 18 years of age. In order to join, the applicant must receive recommendations from two current ISDEF members. There is no special form or procedure required for obtaining these references. The important thing is that when the application is being processed these members can confirm the recommendation.

In order to apply for ISDEF membership, an application form (russian) must be filled out.

Applications are reviewed by the ISDEF Board of Directors within 3-6 days following their submission. The decision to accept a new member is made by simple majority vote among Board members. The newly-accepted ISDEF member must pay an annual membership fee of 100 USD within two weeks of the positive decision (payment is made based on the exchange rate posted by the Central Bank of the Russian Federation on the day of payment).