Out-of-Home (OoH) media has always been in trouble regarding measurements. Although great effort, resources, money and time has been spent in many countries, the complexity of the media - due to its geographical dispersion, volume and granularity - have been a headache for most researchers. The OoH medium has been difficult to measure due to its inherent nature to spread across the country, with each location measuring differently so that averages or simple models do not suffice to show the true potential of the medium. Methods for measuring trips to the locations of OoH audiences have evolved from paper questionnaires, to telephone interviews, to computer-assisted, to tablet- assisted, to using small GPS devices carried by respondents. In all cases, it was always previously expensive and slow. Therefore, when new requirements suddenly appear, due to the digital king, it makes the current OoH methodologies appear old, even to more senior research participants. Of course, this impacts the perceptions of the media itself, as the media planning tool lacks the advantages of other media such as fresh data. We think that only with the mix of several data sources, each one contributing its strength, can we provide the accurate information that we need for our goal: a worldwide OoH audience measurement.