Book excerpt: How can we approach the complex United Nations system, a ‘family’of principal organs, subsidiary organs and specialized agencies? Where do we get summarizing information on the large number of reform concepts developed and implemented since the late 1990s, in particular in connection with the UN World Summit 2005? The present book provides orientation and information: It is the second updated English edition of the German "Lexikon der Vereinten Nationen". The book provides in addition to concise and comprehensive information on the UN system insight into recent UN developments and reform efforts in the face of global opportunities and challenges, such as the Millennium Summit 2000 and World Summit 2005, and the establishment of important new UN organs, the Human Rights Council and the Peacebuilding Commission, in 2006. The contributing authors are academic scholars of international law, economics and political sciences; active and former diplomats and UN officials; journalists and members of non-governmental organizations (NGOs), and offer a variety of interesting perspectives. The entries are provided with bibliographies and with Internet addresses for further information and are supplemented in the annex by an informative text on the UN document numbering system and by a list of information facilities concerning the UN. This title was reviewed as „essential“ (highest category of recommendation) by Choice – Current Reviews for Academic Libraries in October 2010. 'A new edition of a mammoth, 900-page-plus encyclopedia covering every aspect of the United Nations and its work is now available in English in the United States... Among its many useful features are exhaustive lists of those bewildering UN acronyms, a key to decoding (and thus knowing how to look for) UN documents and a complete copy of the UN Charter. The easy-to-use alphabetical order of entries makes it easy for schoolchildren and adults to navigate.' Barbara Crossette in: The InterDependent, 4 October 2010 (www.theinterdependent.com). 'This multidirectional compass is extraordinarily well researched and written. It is a veritable research dream, without which no international collection could possibly be complete'. American Society of International Law, Newsletter of the UN21 Interest Group, January 2011 'This is an update... [of the 2002 edition], with articles contributed by a number of experts on the United Nations and international relations. Entries are either wholly updated or the original article is updated with a signed addendum, making the information current as of the end of 2008. Articles are very detailed and include copious references to other parts of the volume, indicated with an arrow. Most entries conclude with a bibliography of works useful for further research, many of which are extensive reviews of the literature on a particular topic in multiple languages. Entries range from overviews of the workings of the United Nations (including budget, membership rules, and organization) to more theoretical discussions of international law. ...[The book] will be indispensable for any research university with faculty in international relations or law. Summing Up: Essential. Graduate students and researchers/faculty. T. Miller, Michigan State University, Review in October 2010 in Choice – Current Reviews for Academic Libraries.'