How do you capitalise on a market that spans more than 20 countries, 1,000 tribes and languages and where observing cultural differences is crucial if 350 million-plus consumers are to believe your ads' authenticity?
This is the challenge faced by agencies and advertisers in Central and West Africa, which despite the disruption of years of conflict, is seen as the new land of opportunity.
Most of the networks, such as Saatchi & Saatchi, Y&R Brands, TBWA, Ogilvy (which recently launched Vodafone in Ghana) and DDB, have a strong presence in these markets - from Senegal in the West through to oil-rich Nigeria, with its population of 150 million and an annual $600 million adspend, to Cameroon in the East of the region.
Some have an African hub in South Africa and most networks use partnerships and affiliations with local agencies through which to gain insight and understanding of the local market in return for the networks' resources and name.
Last month, Publicis broke the mould by opening a wholly owned agency in Ghana to serve 22 markets in Central and West Africa. It is staffed by a team with the kind of international experience that would be respected anywhere in the world and led by Kofi Amoo-Gottfried, the former Wieden & Kennedy senior planner, who grew up in the Ghanaian capital, Accra, where the agency is based.
Amoo-Gottfried, the managing director, is joined by Promit Moulik, the former Lowe India executive creative director, in an equivalent role.
The structure of this agency is a strong signal to clients such as Nestle, Procter & Gamble, L'Oreal and Orange that Publicis is serious about the region. Richard Pinder, the network's worldwide chief executive, wants the agency to be at the forefront of creativity.
"My observation," Pinder says, "is that, until a nation has found its advertising voice - the way it expresses its culture through communications - it defaults to what I would call 50s American advertising. It happened for the UK when Collett Dickenson Pearce changed things in the 70s. Thailand's time was in the 90s and India's was five years ago.
"The great thing about having someone of Kofi's stature and the team around him, is that we've got people in Africa who I would be proud to have in any of my top ten agencies. And we might even find the advertising voice of Ghana."
Pinder chose Ghana, where last year's annual adspend totalled $140 million, because its history of political stability means that it is somewhere clients are flocking to.
The main languages in the region are English, French and Portuguese, but, Amoo-Gottfried says, sometimes ads are adapted into local languages in countries such as Ghana and Senegal.
It is important to remember that religion is important to the nation as a whole, whether the faith is Islam, which is predominant in the West African interior and West coast, or Christianity, which is more prevalent in coastal regions of Nigeria, Ghana and the Ivory Coast.
In ads, too much bare flesh is a no-no as is an affiliation to a political party, Marie Jamieson, the international strategy director at TBWA, points out. "And be careful of humour and sex, because what is funny in Nigeria is not necessarily funny in the Democratic Republic of Congo. Africans are more conservative than Europeans," she adds.
One way of getting past some of the differences is to come up with a campaign that transcends cultures, religions and languages, such as Diageo's Guinness "tornado", a joint effort between Saatchi & Saatchi's London and Cape Town offices, which ran in Nigeria, Cameroon, Ghana and Kenya as well as Ireland.
Simon Francis, the chief executive of Saatchi & Saatchi Europe, the Middle East and Africa, says: "Some insights are universal. 'Tornado' is a big-budget, high-production value movie. It was made using the same director and production team and production techniques as the movie Twister. It's probably the continent's most expensive commercial and that's not what you expect from Africa."
This style of ad goes some way to answering the question about the level of sophistication you can expect from consumers. Chris Harrison, the Africa and Indian Ocean chairman of Y&R Brands, says: "One of the hurdles to effective communication is the tendency of clients to dumb down the messaging on the basis that people won't understand it. We say underestimate consumer knowledge, but never underestimate their intelligence."
Another issue worth considering is life expectancy, which ranges from 41 among men in Angola to 65 for women in Senegal.
Patrick Ehringer is the EMEA president at DDB. Its work includes a print campaign for Crown Paints in Kenya and Uganda.
He explains: "People are young compared with developed countries where the average age is 35. In these countries, the average age of the population is 18, so it gives you another target."
This might explain why some of the most successful campaigns have a youthful feel. The Diageo-owned soft drink Malta Guinness has been pushing boundaries with a street dance competition, which is broadcast on TV.
Another Guinness innovation was the creation of Michael Powers, a James Bond-style character, who featured in four five-minute commercials. They became so popular, it was turned into a feature film.
While advertisers may not get away with so blatant an example of branded content in other parts of the world, Diageo says it takes self-regulation very seriously. The company says it follows the same guidelines on issues such as responsible drinking as it would in countries with tougher restrictions.
The other benefit of the street dance concept is that it's not limited to traditional media, which is difficult to monitor. While affluent families own TVs, in poorer areas it is not unusual to find a whole community crowded round a 15-inch screen. And because electricity shortages are common, advertisers must run a high frequency of commercials to reach people.
Billboards are popular (Nigeria alone has 20,000 sites), but with 65 million illiterate West African adults, too much copy will have limited impact.
Radio is accepted as the most universally consumed media, even in the poorest rural areas, mainly because it is becoming available through mobile phones.
According to figures from Wunderman, there are more than 35 million mobile subscribers in Nigeria and about seven million in Ghana, which has a population of about 24 million.
Given these figures, it is unsurprising that mobile brands such as MTN, which uses DDB Lagos to create its advertising, are among the biggest advertising spenders.
Despite the complexities of the region, there is huge potential in Central and West Africa that networks ignore at their peril.