From April 18th through May 10th, Watson Library will be open to all current graduate students, undergraduates in economics, faculty and staff from 8am to 7pm, Monday through Friday,
At all other times during these two weeks, i.e. after 7pm until close and all open hours on Saturday and Sunday, access to Watson Library is available to all University affiliates.
If you need materials or services during the 8am to 7pm restricted period designated above and you are not in one of the groups listed please ask a library staff member for help. Study space is available in Butler Library, Lehman Library, and the Science and Engineering Library. http://library.columbia.edu/services/study-spaces.html