The study aimed to identify what interlending is in university libraries, its objectives and features, and to present a set of regulations and rules governing interlending in university libraries globally and in the Arab world. A set of regulations and rules governing interlending in university libraries globally and internationally, and highlighting On the interlending service in the unified catalogue of Egyptian universities by identifying the practical application The researcher also presented a set of experiences that dealt with the service globally and internationally. The researcher presented a set of experiments that dealt with the service globally and in the Arab world and identified the most important results and recommendations from them, in addition to identifying the opinions of The researcher presented a set of experiences that dealt with the service globally and internationally, in addition to identifying the most important results and recommendations from them, in addition to identifying the opinions of university library managers about the activation of the service. overcome them. The researcher adopted the empirical approach to achieve the objectives of the study.