This is a non-exhaustive list of principal conductors by orchestra, principally for orchestras with pages on Wikipedia, classified by country and by city. The term 'principal conductor' is used here as an umbrella term to encompass such titles as:
The term 'music director' is more common in the US and Canada, whereas 'principal conductor' or 'chief conductor' is more prevalent elsewhere. For orchestras which have both a music director and a principal conductor, such as the Royal Northern Sinfonia and Orchestra Sinfonica di Milano Giuseppe Verdi, the person with the title of music director is given preference by hierarchy.
Orchestras which choose not to have principal conductors, such as the Orchestra of the Age of Enlightenment, Saint Paul Chamber Orchestra and the Vienna Philharmonic Orchestra, are omitted from this list. Likewise, principal conductors for opera companies are omitted, unless the orchestra of that opera company performs orchestral concerts under a separate name.