If you have ever encountered an abbreviation or acronym you feel pretty sure refers to an organization but could not figure out what the actual name of the organization might be, this book will help. It is more than a beginning -- there are thousands of organizations known by their initials or acronyms included -- and it is particularly useful for smaller or more obscure organizations that were around before internet search engines changed the way we research most things for which we need a fast answer.The geographic focus here is the United States, although many organizations in other countries are included. English is also the language on which the book is based. (However, the oldest organizational initialism given is one familiar to anyone who studied Latin: SPQR -- Senatus Populesque Romanus -- the Senate and the Roman People, an initialism seen in most depictions of Roman Legions.) Organization is alphabetical. All you need to know to use the book is the acronym or initialization about which you are curious. When you find the abbreviation or acronym, you'll see all the occurrences the author has been able to document for that string of letters. Interestingly, many acronyms apply to more than one organization, and one abbreviation listed has been applied to no fewer than 16 separate groups. For nearly all abbreviations listed there is also a categorization to help further research -- perhaps a labor union, or a mutual benefit society, or a railroad, or a university, or a social club. This book is a resource for the researcher - or the casual reader, for that matter -- who wants some possible meanings and can take things from there. It can help find the organization that might appear on the 15th page of Google results, and, since many of these organizations existed long before the internet, not be known to the search engines at all. There's also a helpful introduction providing more information about organization types and specialized sources for further research, should it be necessary to pin down the organization in question more conclusively.