Become a Member

Membership & Local Support

IPWSO was established so that PWS associations, families, clinicians and caregivers around the world could exchange information and support and have a united global voice under one umbrella. 


Please see our Constitution for further details.

Member countries are subscribed members with voting rights and Associate Member Countries have professional and/or parent contacts who are working with people with PWS. 


In order to contact the local representative or delegate of any member countries or associations, see our Country Members page.

Why join IPWSO?

Together we have a strong, global voice to call for better care, support and awareness of PWS.

Global Voice

Together we can support each other. Our network of members ranges from old, well established organisations to brand new ones! We can support and guide your development as an association and give you access to our expert networks.

Support Network

Together we can support people in countries where there is no association and where knowledge and access to care may be very limited.


Together we can make the global PWS community aware of the many free services, including diagnostic testing, offered by IPWSO.


Together we are IPWSO. Have a say in how IPWSO is run at our General Assembly and get more involved in our events.

One Organisation


All fully subscribed country members with their own constituted PWS Association pay an annual subscription fee based on the number of families in their membership.  The subscription year runs from 1 January to 31 December.


To join us, get in touch.


Membership fees

Country Associations with less than 50 members   EUR 50

Country Associations with  50-99 members            EUR 100

Country Associations with 100-299 members         EUR 200

Country Associations with 300-499 members         EUR 500

Country Associations with 500+ members              EUR 1,000

All subscribed country members have voting rights at the General Assembly which is held every three years in conjunction with the IPWSO International Conference.

Countries where there is no constituted PWS Association, but where there is either (or both) a Professional Delegate, or Parent Delegate may claim Associate Membership.  This entitles these delegates to receive all information, support, and educational knowledge from IPWSO via our Newsflash, social media, or direct access to IPWSO and its boards for help and support.


Associate Membership does not entitle voting at the General Assembly.



Associate Membership of secondary PWS Associations

Where there is another PWS Association or organisation in a country, this association or organisation can apply for IPWSO Associate Membership and receive the same benefits and access to IPWSO as ordinary Associate Membership (above).  There is also an entitlement for a Parent Delegate, a Professional Delegate, and a Caregiver Delegate as representatives of the Association.  However, there is no entitlement for voting at the General Assembly as any voting decision must be made in conjunction with the primary PW Association of that country.


IPWSO Delegates

Each country's registered PWS Association appoints Parent and Professional Delegates to be their representatives.  When applicable, a Caregiver Delegate  is also appointed. 

Associate Membership

Further information:

> Country Members

> About us

> IPWSO Delegates

> IPWSO Advisers

> Our Trustees, Boards and Staff

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Registered as a charity in England & Wales, charity no. 1182873