In 1959, Rolls-Royce acquired H. J. Mulliner & Co., coachbuilders (HJM). In 1961, HJM was merged with Park Ward, which had been in the possession of Rolls-Royce since 1939, to form Mulliner, Park Ward Ltd. (MPW). When production of the S3 Continentals commenced there were more differences than the adaption of the previous HJM design by Mulliner Park Ward: The cars were built at the former Park Ward premises in Willesden, North London. The HJM facilities were abandoned.
The S3 Continental was strictly coachbuilt. Most bodies were of the altered HJM style, available in fixed head or drop head coupe form. Of the 328 coachbuilt S3 (Continentals included here), nearly 100 were by MPW. Again, fixed head or a drop head coupe configurations were available. The most prominent visual difference from the S2 configuration was the four canted headlights.