John Dimling, a 16-year Nielsen Media Research veteran and its CEO for the last four years, is retiring at the end of the year and will be replaced by Susan Whiting, who was named president and chief operating officer in May.
Dimling, 63, will remain with the company on a part-time basis, with the title of non-executive chairman for both NMR and AC Nielsen International.
It was on his watch as head of Nielsen's national TV-ratings service that NMR transformed the TV-ratings business with the 1987 introduction of the Peoplemeter. He also oversaw the expansion of metered measurement from eight markets in 1985 to 53 markets today and the launch of Nielsen's Hispanic ratings service in 1992 and Internet ratings service in 1999.
Whiting, 45, is a 23-year veteran of the company. She was part of the team that developed the Nielsen Home Video Index division for measuring cable television and became its vice president in 1986.
In 1997, she was named general manager of national services and emerging markets. Dimling said she represents "a continuation of this company's core values ... she is a natural leader and a team builder with remarkable business savvy."