Formed in 1961, the Register has two aims.

The first is to keep track of all known SS, SS Jaguar and Jaguar cars manufactured from 1931 to 1952, except XK120s and Mk VIIs. The object is to keep a record of all these cars worldwide, and to ensure it contains the maximum number of, and the most accurate data about, all surviving cars. The JDC records have been added to with the listings from the USA, Australia, Austria, New Zealand and Switzerland. This has expanded the numbers in the database to 2103, and as at 31st December 2006, the numbers per model were as follows:

SS1 (all versions) 254

SS2 (all versions) 57

SS90 18

SS100 288

SS Jaguars (all saloons, tourers and dhcs) 1936-40 304

Jaguars 1945-9 (Mk IVs) 484

Mark V 698