Toronto's MaRS Centre has changed in many ways since the front doors on College Street opened in September of 2005. More than 2,000 people, representing over 65 tenants, come to work at the Centre every day, and many more come to participate in workshops and programs. On any given day, Canada's leading researchers unravel the mysteries of biology in state-of-the-art labs throughout the Toronto Medical Discovery Tower and the Ontario Institute for Cancer Research; innovative early-stage companies put business plans into action in the MaRS Incubator; organizations across the innovation spectrum grow their businesses in the Heritage Building—the original brick facade of the old Toronto General Hospital. From the earliest of start-ups to some of the biggest names in Canadian business, all call the MaRS Centre home.