The UK has the most developed club network, with organisations covering virtually the whole country.
Elsewhere, local clubs can often function as national branches simultaneously, such as IPMS Argentina who also represent the Mar del Plata region of the country.
In addition to the branch and club structure, Special Interest Groups (SIG) exist which focus on a specific area or type of model building, for instance a particular aircraft such as the Tornado, a time period like the Cold War, a manufacturer such as Airfix or a genre like science fiction and fantasy.
SIGs often transcend club and branch boundaries, being made up of modellers from around the world sharing a common interest.
As a result, most SIGs do not meet up on a regular basis like clubs, but instead communicate more frequently online.