The findings of a study of Millennials in the US and the UK—an increasingly important and digitally savvy segment of consumers—reveals that they see advertising as Companies promoting a product or service to people through media. Their perception is simple and all-encompassing with no evidence that they distinguish between different types of media or different types of communication. Some variation between the views of Millennials in the two countries is also identified, although this is less than expected. The findings contribute to an important and continuing debate among academics and marketing practitioners over how advertising should be defined in today’s multi-channel environment. The findings are also compared with other recent definitions of advertising and their implications are discussed.