The Periodicals Department deals with newspapers, directories, travel guides, and many numbered series of reports and monographs as well as periodicals (journals, magazines, etc.) as commonly understood. It does not handle governmental or inter-governmental publications (for which you should enquire in the Rare Books Reading Room) nor periodicals in Far Eastern scripts.
Under the provisions of UK copyright legislation (currently The Legal Deposit Libraries Act 2003 ) the University Library is entitled to claim copies of all periodicals currently published in the British Isles. In practice it seeks to claim all periodicals of possible academic interest and a selection of the remainder. Some periodicals are sent direct to the Library by their publishers but most are forwarded to it by the Agency for the Legal Deposit Libraries in Edinburgh. It follows that current issues may not reach the Library until some time after publication. Foreign periodicals are acquired selectively by purchase or donation. Forms are available at the Enquiry Desk to recommend the acquisition of periodicals not already held or made electronically by clicking http://www.lib.cam.ac.uk/book_recommend.php.