One of the objectives of the ISI is to facilitate collaboration among diverse groups of ISI members, statistical societies and other national and international organisations with statistical interests. 

In pursuit of that purpose, ISI provides three types of membership: 

• Individual membership
• Organisational membership 
• Affiliated membership

All members of ISI share the values and objectives of the ISI. 

Individual Membership

There are three types of individual membership:

• Regular membership
• Elected membership
• Ex-officio membership

Any individual can become a regular member of the ISI by applying for membership. 

For elected membership, an individual (regular member or potential new member) must be nominated. Elected members shall have made significant contributions in one or more of the following areas: statistical research, practice, education, administration of statistical service, or the promotion of the profession. The nomination and election processes are specified in the By-laws. 

All individual members have voting rights. 

Regular and elected members must pay annual dues which is determined by the Council. 

Organisational Membership 

There are two categories of organisational membership: 

• Institutional membership
• Affiliate membership

National, regional and international statistical institutes/agencies as well as central banks and private organizations may become institutional members of the ISI. 

Each organisational member is entitled to designate one person as an ex-officio member, who will have all the rights of individual membership. Any non-profit organisation, including national or regional statistical societies, may become an affiliated member of the ISI, subject to approval by the Executive Committee.

The Executive Committee is responsible for all final decisions on applications for membership.

General Assembly

The General Assembly which is the highest authority within the ISI is composed of all individual members of the ISI.