Symphony Nova Scotia, Halifax, Canada – music director from 2002
Johannesburg Philharmonic Orchestra – principal guest conductor from 2009
Nuremberg Symphony Orchestra, Germany – music director August 2005–July 2009
Cape Town Philharmonic Orchestra – principal conductor 1997–2000

RSO Stuttgart
RSO Oslo
RSO Stockholm
City of Barcelona Symphony Orchestra
Adelaide Symphony Orchestra
Orchestre-de-Bretagne, Rennes, France
Orchestra of the Loire, France
Stuttgart Philharmonic Orchestra
Stuttgart Chamber Orchestra
German Brass
Kanagawa Symphony Orchestra, Yokohama
Sapporo Symphony Orchestra, Japan
Nashville Symphony Orchestra
Nurnberg Symphony Orchestra
Novosibirsk Symphony Orchestra, Russia
Rananna Sinfonietta, Israel
Cape Philharmonic Orchestra
Shanghai Symphony Orchestra
Guangzhou Symphony Orchestra, China
Hong Kong Sinfonietta
Johannesburg Philharmonic Orchestra
Kitchener Waterloo Symphony Orchestra, Canada
KZN Philharmonic Orchestra, Durban
Pori Symphony Orchestra, Finland
South African National Youth Orchestra
Seoul Philharmonic Orchestra
Edmonton Symphony Orchestra
State University Orchestra, Milan
University of Cape Town Symphony Orchestra
University of Stellenbosch Symphony Orchestra

As principal conductor of the Cape Town Philharmonic Orchestra, Gueller led its participation in 2000 in the 16th International Festival of Music in the Canary Islands, where the CTPO represented the continent of Africa. He took the Nuremberg Symphony Orchestra on a tour of several cities in northern Germany, giving a concert in the Berlin Konserthaus.