The Orchester Musikkollegium Winterthur is a Swiss symphony orchestra based in Winterthur, Switzerland. The oldest orchestra in Switzerland, it was founded in 1875 as the Stadtorchester Winterthur. The Musikkollegium itself, as an organisation based out of religious roots to that time, was founded in 1629. The orchestra performs around 60 concerts a year, and in addition to orchestra concerts, performs in the pit at the Zurich Opera.
From 2002 to 2008, Jac van Steen was principal conductor of the orchestra. The orchestra and van Steen made several commercial recordings for the MDG label, including music of the composers of the Second Viennese School and of Frank Martin. In April 2008, the orchestra announced the appointment of Douglas Boyd as its next principal conductor, effective with the 2009-2010 season. The orchestra has since extended Boyd's contract as principal conductor through the 2015-2016 season. Boyd concluded his tenure as principal conductor after the 2015-2016 season. In June 2015, the orchestra announced the appointment of Thomas Zehetmair as its next principal conductor, effective September 2016, with an initial contract of 3 seasons.
In the modern repertoire, the orchestra works often with Heinz Holliger, and in the baroque repertoire with Maurice Steger and Nicolas Kraemer. With Boyd as conductor, the orchestra has made commercial recordings of music of Wolfgang Amadeus Mozart, Felix Mendelssohn, Josef Rheinberger and Ralph Vaughan-Williams. The orchestra has made other commercial recordings with Holliger, and other conductors such as Werner Andreas Albert.