APRIL 1990

Richard A. Gagne, owner of Dental Horizons, in Oxnard, Calif., never used to be sure which of the many places he advertised were generating the most dollars of dental service. Then he started listing different phone numbers -- his office has several lines -- in any advertisements that were running concurrently.

"Now, we always track which ads are drawing phone calls," says Gagne, who compares response rates to ads in different publications, and then allocates his ad budget accordingly.