Seventeen first-year dormitories are located in and near Harvard Yard. Some house students in a single room, but most house students in suites, typically featuring a common room and bedrooms for up to six people. All rooms and bathrooms are single-sex; many bathrooms are used by all the suites on a single floor, others are shared by adjoining suites, and some are accessible only to a single suite.
Harvard guarantees housing all four years and during their last three years students live in a single House community, which ranges in size between 350 to 500 students. At the end of the first year students choose friends with whom to block in the Housing lottery, which guarantees their placement together in one of the twelve residential Houses. As in the Yard, rooming groups and bathrooms are single-sex and students generally live in suites of rooms. Each House has its own library, dining hall and common rooms, and also offers a wide range of formal and informal advising resources in its resident and non-resident tutors and faculty fellows.