Companies are ranked according to their percentage increase in sales during the previous five years, in this case, 1979-83. To be included in the INC. 100, each company must meet the following criteria:

1. The company is an independent, publicly held corporation in a manufacturing, mining, or service industry. Utilities, banks, and other financial institutions are excluded.

2. The company was publicly held as of December 31, 1983.

3. The company shows an operating/ sales history of at least five years, with an increase in its fiscal 1983 closing figure. Companies showing growth in the 1979-83 base period but a sales decline in the last year are excluded.

4. The company's 1979 sales were at least $100,000 but less than $25 million.

Company data is gathered from prospectuses, 10-Ks, annual reports, and various directories. Additional information is collected from a wide array of newsletters, trade magazines, and other business publications. Telephone interviews are conducted with executives of the corporations to verify the figures.

By applying the four criteria listed above, and by using a five-year growth rate of at least 400%, INC. reduced the number of companies that potentially qualified for the list from 13,000 to 194. Among those considered were 888 companies that went public in 1983.

An editorial team led by senior editor Bradford W. Ketchum Jr. selected the 1984 INC. 100. Chief researcher was Nell Margolis, assisted by Susan Buchsbaum, Donna Fenn, Julia Homer, and Joshua Hyatt. Data processing was directed by Elyse Friedman, senior research editor.