The letters in this volume record an important transition in Brandeis's life. In July 1907, when the letters begin, Louis D. Brandeis was merely an unusually successful local reformer. His earlier victories against the Boston Elevated and the Boston Consolidated Gas Company, even his stunning success in the achievement of the Savings Bank Life Insurance law in Massachusetts, all centered exclusively upon Boston or Massachusetts problems. But by December 1912, when this book ends, Brandeis was one of the best known social activists in the United States.

He received regular national attention in popular periodicals and advised the newly elected President of the United States. As these letters show, Brandeis always kept one eye on Massachusetts affairs—supervising the inauguration of the insurance reform, continuing to oppose long-term franchises for the subway, and advising Massachusetts governors on proposed bills and prospective appointments. But he devoted the major part of his energy in this five-and-a-half-year period to a series of crusades of crucial national importance.

He attacked the attempt of Mellen and Morgan to gain a monopoly hold over new England transportation as he strenuously and doggedly opposed the merger of the Boston & Maine with the New Haven railroad. He entered, in a leading role, the most celebrated conservation battle of his generation, the Pinchot-Ballinger controversy, and he emerged as a major spokesman for the preservation and orderly development of natural resources. He helped to hammer together an arbitration mechanism to maintain industrial peace within the New York garment trades, a mechanism he believed would have broad implications for the future of industrial democracy in America. He battled the demands of the railroads for increased rates; he joined the crusade for efficiency and scientific management; and he directed repeated blows against the huge concentrations of economic power within the national economy.

It should not be surprising that Brandeis and Robert M. LaFollette were drawn together, and these letters will show both the extent of that relationship and the way in which Brandeis's influence spread to other progressives in Congress. Other matters—his earliest Zionist activities, his achievement in defending progressive state legislation before the Supreme Court, his interest in Alaskan development along conservationist lines, his plan for the regularity of employment, his role in the Presidential campaign of 1912—are all part of his work during these turbulent years and are all touched upon in greater or lesser detail in these letters.