The Association of Independent Railways (AIR) succeeded the Association of Minor Railway Companies (AMRC) in 1988, and was one of the preservation movement’s two controlling associations. It represented the views of heritage railway companies and their management. Membership of the AIR was open to independent railways; the association having inherited the members previously registered with the AMRC.

Its aims were to promote the common interests of heritage and preserved railways at local and national level, as well as represent the movement on matters of legislation. The AIR continued the coordinating and publicity remits of its predecessor, and also assumed responsibility for the Railway Letter Service, which permitted the posting of letters at railway stations for conveyance by train until it could be posted at a location near to the addressee for an extra charge.

A Board of nine Directors was chaired by the railway publisher Ian Allan. Allan was instrumental in implementing the merger with the Association of Railway Preservation Societies (ARPS) proposed by the Lawrence Report of 1995 which led to the creation of the combined Association of Independent Railways and Preservation Societies (AIRPS) in 1996.