Broadcasters that have signed long-term commitments include Grupo ACIR, Imagen Telecomunicaciones, MVS Radio, Nucleo Radio Mil, and Organizacion Radio Formula. These broadcasters operate 23 stations in Mexico City and the Valley of Mexico. Advertising agencies and media buying services that have signed contracts or letters of intent include BBDO - OMD, Control Media, FCB Worldwide, Initiative Media, Leo Burnett - Starcom, McCann Universal, Media Planning Mexico, and Mindshare. These agencies account for more than two-thirds of radio ad spending in the Mexico City radio market.

According to Steve Morris, president and CEO of Arbitron, "We are honoured that Mexico City broadcasters and agencies have invited Arbitron to create a new standard for radio audience measurement in their booming media marketplace. We have worked hard to demonstrate the value of our diary-based ratings service; the integrity and objectivity of our people and processes as well as the advantages of the Arbitron name as a provider of ratings information to the sellers and buyers of radio advertising. Our expansion into Mexico City continues the steady growth in our core radio audience business that we have sustained over the years. While the consolidation in the US radio industry has slowed, we continue to identify new ways to utilise our core competencies and infrastructure."

Each quarter, beginning in September 2001, Arbitron will use a Spanish-language version of a standard seven-day radio diary to survey the radio listening behaviour and key socio-economic characteristics of approximately 4,800 Mexico City residents, aged 12 and older. In-person interviewers will place the diaries at the households selected to participate in the survey and later retrieve the diaries at the end of the survey week (This differs from Arbitron's practice in the United States that uses telephone interviewers to recruit survey participants and the US mail to place and later retrieve diaries for processing). Collected Mexico City diaries will be shipped to Arbitron's Columbia Research and Technology Center for processing and tabulation using the company's existing processing infrastructure, which has been adapted to handle the Mexico City diaries.

The first data from the Autumn 2001 Mexico City radio survey will be released in February 2002. Thereafter, Arbitron will deliver monthly reports of the Mexico City audience based on a rolling average of the three most recent months being surveyed. All audience information will be delivered via software applications only.

Arbitron's proprietary research shows that radio in Mexico City is a very powerful ad medium with a constant presence in the lives of Mexico City consumers. According to Clara Carneiro, vice president of Arbitron Latin American Marketing, "Nine out of ten Mexico City residents are reached by radio each week. Compared to the US, Mexico City residents spend a higher proportion of their daily media time with radio than their American counterparts – 53% for Mexico City versus 44% for US residents."