Philip Morris International Inc. (PMI) is a Swiss-American multinational cigarette and tobacco manufacturing company, with products sold in over 180 countries.[3] The most recognized and best selling product of the company is Marlboro.[4] Philip Morris International is often referred to as one of the companies comprising Big Tobacco.

Until a spin-off in March 2008, Philip Morris International was an operating company of Altria. Altria explained the spin-off, arguing PMI would have more "freedom," i.e. leeway outside the responsibilities and standards of American corporate ownership in terms of potential litigation and legislative restrictions to "pursue sales growth in emerging markets", while Altria focuses on the American domestic market.[5] The shareholders in Altria at the time were given shares in PMI, which was listed on the London Stock Exchange and other markets.

The company's legal seat is in Stamford, Connecticut but it does not operate in the United States of America. Philip Morris USA, a subsidiary of PMI's former owner American parent Altria group, owns the Philip Morris brands there. Operational headquarters are in Lausanne, Switzerland.[6]

With tobacco being addictive and the single greatest cause of preventable death globally,[7] the company is highly controversial, not least because of its history of obfuscating scientific evidence around the health impacts of smoking. It has been the subject of litigation and restrictive legislation from governments.

In response to awareness of the harm to health of cigarettes, PMI has declared on its homepage the intention to replace cigarettes with smoke-free products, and to "switch ... adult smokers" to these products as the first phase of a business strategy, as a decision for the benefit of "adult smokers" and the company's shareholders and employees.[8][9][10]

With the world-wide decrease in smoking prevalence in the 21st century, shares of Philip Morris were no longer considered the "safe haven" they once were.[11] However, it has to be noted that the absolute number of smokers continues to increase. The company ranked No. 101 in the 2021 Fortune 500 list of the largest corporations by total revenue.