There are two airports which serve the city of Toronto: Toronto Pearson International Airport (YYZ) and Billy Bishop City Airport (YTZ).
Billy Bishop Airport is on the water-front (in the heart of the city) and it costs approximately $15-$20 for a taxi ride from there to the venues for the Clinical Days.
Pearson Airport is north of the downtown core and it is approximately $50 for a taxi from there to anywhere downtown. Alternatively, there is a high speed express train -- the Union Pearson Express -- which will take you from the airport to multiple locations downtown. The train's final destination from the airport is Union Station and the fare to get there is $12.65 (one way).
The one main train station in downtown Toronto is Union Station and it is served regularly by VIArail (Canada) and Amtrak (U.S.A.). Union Station is the main transit hub in Toronto and you can find a taxi or catch the subway (known as the TTC) to anywhere in the city from here. For more details on the TTC, click the button below.
The main highway into the Greater Toronto Area (GTA) is the Trans-Canada Highway / HWY 401. This highway travels east-west and the easiest artery into the city of Toronto from the 401 is the Don Valley Parkway (DVP = HWY 404 South). For the downtown core, travel south on the DVP, exit at the Bloor Street off-ramp and travel west on Bloor Street. The Clinical Days venues are all within a few minutes of walking from the corner of Bloor Street and St.George Street. See "Getting to Clinical Days" on this website for more detailed information.