Affordability measures the price of a product relative to a measure of income. Affordability has grown in prominence in the tobacco control literature in recent years as global tobacco consumption has shifted from high-income to low- and middle-income countries. As many low- and middle-income countries are achieving unprecedented rates of economic growth, increases in income are making cigarettes rapidly more affordable. As such, measuring the affordability of cigarettes over time has become an important anchor for tobacco tax policy. While affordability measures over time are very important, the comparison of affordability across a group of countries is not particularly useful since incomes vary far more substantially across countries than cigarette prices. Therefore, making between country comparisons using affordability has limited use. For between country comparisons, comparable cigarette prices measures are more important.