The rapid growth of digital media over the past 10 years has completely reshaped the media planning landscape, challenging the way that media planners used to think as they rolled out the advertising strategies for their clients. Today, it's all about quality of audience and engagement rather than pure reach.

That's according to Marcus Stephens, general manager of Howzit MSN, one of South Africa's largest Web portals by audience size. He says that the mass media model of the past where companies broadcast a message to a large audience is giving way to a model where they speak to smaller but more targeted audiences.

Says Stephens: "Media planning used to be easy - you'd choose the print or broadcast outlet that offered the best match with the advertiser's brand and target market. You would broadcast the same advertising message to millions of people in the hope that it would drive a response from a few thousand of them.

"Cost-effective production, duplication and distribution of content used to be the main concerns for any advertiser. Now, however, the challenge is all about capturing the divided attentions of an increasingly fragmented customer base that is increasingly migrating online for its entertainment and information needs."

Stephens says that with around seven million South Africans consuming online media, the country's market for Internet content has grown to the same size as its population of DSTV viewers. This is a large and growing market that companies should not ignore, but they cannot address it in the same manner as they used to the mass media market of old.

DSTV has around 160 channels, but Internet users have some 2.5 million Web sites to choose from. With smaller pockets of audience spread across more media outlets, brands need to think strategically about who they want to reach and how they want to talk to them.

"But this shift in the market brings with it some excellent opportunities for media planners to improve their clients' return on investment from advertising spending," says Stephens. "We can target creative messages at the audiences we want to reach more accurately, enhancing the impact of advertising while bringing down the costs of engagement. We can talk to the people we want to talk to rather than paying to reach millions who are not in our target market. And we can collect data about the audience and our ads that help us to constantly improve return on investment."

Stephens says that rich data is the key to getting the most from digital advertising since it allows companies to understand how effective their advertising is, which messages work best, which outlets their customers come from and the path that customers follow to conversion.