Habitat 67 is the name given to the experimental urban residential complex designed by Israeli-born architect Moshe Safdie on Mackay Pier opposite the City of Montréal's Old Port sector. Commissioned by the Canadian Corporation for Expo 67, the project derives its name from the theme of the fair, "Man and His World," and evolved as one of the major pavilions of the exhibition. It is the sole pavilion of the fair to retain its original function.

The design of the complex stems directly from Moshe Safdie's undergraduate thesis research while an architecture student at McGill University's School of Architecture. In a report he wrote the summer of 1960 while travelling on a grant funded by the Central Mortgage and Housing Corporation, "A Case for City Living. An Investigation into the Urban Dwelling for Families," Safdie probed alternatives to suburban sprawl by rethinking the urban habitat as an affordable, mass-produced dwelling that provided direct access, privacy and a garden for every resident.

In its built form, Habitat 67 is an iconic cluster of 354 interconnected concrete boxes stepped and stacked in a slightly pyramidal structure rising 12 storeys. The modules are held together by a system of post-tensioned cables, and are variously configured to permit a variety of sizes and layouts. Typically, dwellings range from 1-bedroom (600 ft2) to 4-bedroom (1700 ft2) units, spanning 2 levels. At its inception, the complex housed 158 units - a mere fraction of the 1200 originally planned by Safdie. Serviced by 3 elevator cores, pedestrian streets on the 2nd, 5th, 6th and 10th floors run the length of the complex and provide the main circulation paths from which residents gain direct access to their homes.

Of the several innovations inaugurated by Habitat 67, the complex's conception as a continuous, 3-dimensional urban structure in which all members are load-carrying, an on-site factory for casting the concrete modular boxes, as well as the use of pre-fabricated components such as fibreglass bathroom units and pre-assembled kitchens, are noteworthy.

The success of Habitat 67 spurred a series of international commissions for Moshe Safdie on the same theme: affordable, high-density urban residential communities composed of factory-produced, modular units. These later projects (all unbuilt), for which Safdie continued to explore alternative geometries and innovative technologies, include Habitat New York (New York City, 1967-68); Habitat Puerto Rico (San Juan, 1968-70); Habitat Israel (Jerusalem, 1969-70); Habitat Rochester (New York, 1971); and Habitat Tehran (Elahieh, Iran, 1976-1978).