The Hamilton Street Railway (HSR) is the public transport agency for Hamilton, Ontario. The name is a legacy of the company's early period, when public transit in Hamilton was primarily served by streetcars. Although streetcars are no longer used in the city today, the HSR operates bus and paratransit services, with a ridership of 21 million passengers a year.

The Flyer 700/800/900 series were a series of transit buses built in three generations by Western Flyer and its successors Flyer Industries and New Flyer, of Canada, between 1967 and 1987. Except for brief overlap during transition from one generation to the next, they were not in production concurrently. All individual model designations included a prefix of either D, for diesel propulsion, or E, for electrically powered trolleybuses, with the first digit indicating the generation and the last digit indicating a variant within the generation. The introductory model was the D700, originally released in 1967 for the Canadian transit market, and the last series group to be produced, D900, was discontinued in 1987. Flyer had become New Flyer only the year before, in 1986.