The writer has endeavored throughout to abstain from philosophizing about the I. W. W. He is not unmindful of the fact that the interpretation of such a significant movement as is embodied in the Industrial Workers of the World is of very great importance. Indeed the time has now come when it is urgently necessary. The first intention in writing this book was to incorporate in it an attempt at an analysis and interpretation of I. W. W.-ism, as well as its orientation with other economic isms. But the bony skeleton of historical record has crowded out almost everything else and perhaps filled more pages than its importance justifies. In spite of all this the temptation to comment has been strong and sometimes irresistible. Despite the effort that has been made to be accurate and entirely fair the writer realizes that the book probably contains errors both of fact and judgment. He would greatly appreciate having his attention called to these. The writer is under great obligation to the secretaries of scores of the local unions of the organization in various parts of the country for their valued assistance in the task of gathering the material for this study. He is especially grateful to Mr. Vincent St. John, formerly General Secretary-Treasurer of the I. W. W., for his generous response to repeated requests for documents and information. Thanks are also due for like favors to Mr. William D. Haywood, General Secretary-Treasurer of the I. W. W. and to Mr. Herman Richter, General Secretary-Treasurer of the Workers International Industrial Union (formerly the Socialist Labor Party or Detroit wing of the I. W. W.). Finally the writer wishes to express his grateful appreciation of the numerous and helpful suggestions made during the later stages of the work by Professor Henry R. Seager of Columbia University. He has also to thank Professor Seager and Mrs. C. A. Stewart for their kindness in the tiresome work of reading the proof, and Mrs. M. A. Gadsby, of the staff of the United States Bureau of Labor Statistics, for her assistance in the preparation of the Bibliography. P. F. B. SAN FRANCISCO, JUNE 9, 1918. FOOTNOTES: