SMPS is open to all residents, property owners and merchants who have an interest in preserving and maintaining our beautiful Historic District. The interests of merchants, residents and preservationists are inextricably our South Main Street village its unique character.

SMPS was a key component of the early preservation efforts on South Main and the riverfront. The development of protective legislation, active participation in saving and restoring the Depot, promotion of our history and care for our Historic District village in all aspects... these are SMPS concerns.

SMPS has always been involved in Historic District promotional activities. Festival of the Little Hills, Lewis & Clark Rendezvous (now Heritage Days), Christmas Traditions and Las Posadas ...all were originally SMPS projects. Three Rendezvous in St. Charles events were finally discontinued for lack of funding support: Rendezvous in St. Charles Photo Contest, Rendezvous in St. Charles Concert Series, Rendezvous Ramble. A successful Strings 'n Straw event was held in 2014.

From the SMPS By-Laws. Object:
A non-profit organization founded by residents, shop owners, and property owners in Historic St. Charles, MO for the purpose of contributing to the work of historic conservation, encouraging the economic viability, and the growth of cultural activities in the South Main Historic District, while discouraging any misuse of the South Main Historic District.

SMPS was founded in 1969.