The Columbia-Barnard affiliation continued. Barnard pays Columbia about $5 million a year under the terms of the "interoperate relationship", which the two schools renegotiate every 15 years. Despite the affiliation Barnard is legally and financially separate from Columbia, with an independent faculty and board of trustees. It is responsible for its own separate admissions, health, security, guidance and placement services, and has its own alumnae association. Nonetheless, Barnard students participate in the academic, social, athletic and extracurricular life of the broader University community on a reciprocal basis. The affiliation permits the two schools to share some academic resources; for example, only Barnard has an urban studies department, and only Columbia has a computer science department. Most Columbia classes are open to Barnard students and vice versa. Barnard students and faculty are represented in the University Senate, and student organizations such as the "Columbia Daily Spectator" are open to all students. Barnard students play on Columbia athletics teams, and Barnard uses Columbia email, telephone and network services.