Simpson Thacher & Bartlett LLP began its 124th year in January 2007.

Throughout its history, Simpson Thacher’s practice has reflected the major financial and industrial activities of the times. At the end of the nineteenth and the beginning of the twentieth centuries, the Firm was active in railroad reorganizations, the creation of mining and natural resource companies and the national expansion of the public utility system.

After World War I Simpson Thacher's practice expanded internationally. By the 1920's, the Firm represented clients in Africa, Asia, the Caribbean, Europe and South America.

Simpson Thacher's extensive banking practice developed in the 1950's, with the representation of Manufacturers Hanover Trust Company. Today, the Firm has an unparalleled banking practice representing, among other banks, JP Morgan Chase, the successor to Manufacturers Hanover, Chemical Bank, Chase Manhattan and JP Morgan, each of which was a major money center bank in its own right.

Simpson Thacher has represented investment banks in varied corporate financings from the early 1900's. During the 60's and 70's the corporate practice came to focus more on the financial services sector with the representation of virtually every major U.S. investment banking firm. In the 1980's and 1990's the Firm developed one of the world’s premier merger & acquisition practices, including a unique strength in leveraged buyout acquisitions and finance for clients such as Kohlberg Kravis & Roberts and The Blackstone Group.

Litigation has always been an integral and significant part of Simpson Thacher's practice. Firm litigators focus on trial practice and particularly on jury trials. The Firm’s securities litigation grew after the New Deal enactment of the federal securities legislation during the 1930’s. New antitrust legislation led to a growing antitrust practice by the Firm, with clients in such varied industries as motion pictures, electrical power, steel, plastics and optical glass, can manufacturing, magazine distribution and professional boxing. In recent years, the Firm has played a leading role in multiple-case, multiple jurisdiction litigation and class action cases, as well as international dispute resolution, representing clients from all industry sectors and from around the world.

Simpson Thacher’s commitment to pro bono representation has been well recognized over the years. Recently, Simpson Thacher secured a significant victory for the Campaign for Fiscal Equity when the trial judge in the long-running litigation ordered a $5.6 billion increase in operating aid for the New York City schools and a substantial capital funding increase, following the recommendations of a panel of special masters. This decade-long case represents one of the largest and most successful pro bono initiatives of any major law firm.

The strong commitment of Simpson Thacher and its lawyers to public service has existed from the very beginning. Simpson Thacher lawyers have included U.S. Senators, Solicitors General, a Speaker of the House of Representatives, a Secretary of State, a Secretary of the Army, Ambassadors, Judges on U.S. Circuit and District Courts and the New York State Court of Appeals, presidents of the American Bar Association, and presidents of the Association of the Bar of the City of New York.