Being devoted to one scale means that membership is spread throughout Britain, and several live overseas ( including the webmaster! ) It was recognised at the outset that a regular means of communication was essential to ensure an adequate exchange of news, current trends, ideas and opinions, and to encourage the pooling of expertise. For this reason a quarterly journal called "Mixed Traffic" is distributed to all members. This started out as a couple of duplicated sheets with occasional line drawings. It is now a fully printed glossy booklet complete with halftone illustrations. This is supplemented with a quarterly newsletter which covers reports of local meetings, exhibitions, product news, member's Sales and Wants etc. The costs of the information and administrative services are met from members annual subscriptions.

In some areas of the country like-minded concentrations of members have led to the formation of local Groups that meet regularly. There are 30 Area Groups and each is somewhat informal in character, the scope of activities being decided locally. Area Groups frequently represent the Society at exhibitions using their own layouts and displays, and the Society assists the Groups in these promotional events. The Area Groups have made a substantial contribution towards the growth of the Society. In addition there is an active Great Western Researchers Group.

It is certainly of great benefit to any person wanting to model in 3mm scale to join the 3mm Society. The degree of support offered to members by members is regarded as unparalleled among Scale Societies.