The Symphony Six were a group of Canadian musicians under contract to the Toronto Symphony Orchestra (TSO) who were denied entry to the United States for a concert tour in November 1951. Coming at the height of the McCarthy era in the US, the six musicians – Ruth Budd, Dirk Keetbaas, William Kuinka, Abe Mannheim, John Moskalyk, and Steven Staryk – were denied visas on the suspicion of being involved in communist activities. The TSO sent other musicians in their place and completed its tour.