Harkness is the second-biggest dining co-op (after Pyle Inn), but is very relaxed and welcoming towards guests. In warmer weather most eating takes place outside on the lawn. Meals are often accompanied by music, juggling, and other acrobatics or antics performed by circus-oriented Harkies.
Generally considered among the tastiest of co-ops (at least for the past several years), Harkness won the Iron Chef OSCA competition the first two years (out of three) that it existed, and placed second in 2007. Harkness is also renowned for its artisan bread, quality granola, and craft-brewed beer and soft drinks.
In contrast to the living portion of the building, the co-op's kitchen is consistently rated among the cleanest in OSCA, often earning higher cleanliness scores than Dascomb or Stevenson from the Lorain County Board of Health.
Friday dinner is always pizza night, and is a campus attraction, drawing large numbers of non-Harkies and serving as many future co-oppers' first experience with OSCA. As of 2007, Harkness is the only co-op cooking pizza using traditional methods including a brick oven, starter-based dough, and crust that is tossed rather than rolled. Some have expressed concern that the focus on crust has resulted in decreased output and thus fewer people sharing in the revelry that is Hark pizza. While it cannot claim to have invented the now-pervasive practice among co-op pizza nights of dessert pizzas, Harkness was responsible for elevating the concept. What started as merely sweet ingredients baked atop pizza crusts eventually became proper desserts such as cheesecake and key lime pie - baked and served in pizza pans.
Harkness co-op is also the facility that produces OSCA Tofu.
President Gerald Ford (then a US Congressman) dined at Harkness when he spoke at Oberlin in the early 1960s. This was, however, before the dining facility was a co-op.
Harkness became a co-op in 1967, and has been vegetarian since 1973.
Hartzler's Chocolate Milk, which only comes on Wednesdays, runs out faster at Harkness than at any other co-op.
The Reproductive Health Co-op, which eventually became the SIC, was originally started and housed in Harkness.