BBC News is investigating the changing face of business in Africa, a continent once regarded as a high-risk location for investors but now increasingly a place to do business.
Many in DR Congo and Sudan have economic aspirations
BBC World Affairs Correspondent Mark Doyle assesses the challenges facing the Democratic Republic of Congo and Sudan, two of Africa's biggest countries which have long been beset with internal conflict.
At the busy Congolese town of Kasumbalesa, on the border with Zambia, hundreds of huge 36-wheel trucks thunder down the road every day.
They are leaving Katanga Province piled high with DR Congo's valuable mineral wealth - for processing in the more developed countries of southern Africa, and onward for export.
"Congo is a rich country, very rich," an expatriate mining engineer working near Kasumbalesa told me.
"When we dig paydirt in most parts of the world, we expect to make $200 a tonne. Here in Katanga we expect to make $1,000 a tonne."
Four thousand kilometres north of Kasumbalesa, in the Red Sea city of Port Sudan, a pipeline empties crude oil into tankers.
The pipeline begins in southern Sudan, then snakes across the desert carrying Sudan's oil for onward shipment, mostly to China.
It is believed that up to half a million barrels of crude oil a day are being pumped along the pipeline.
Two countries; both hit by wars and conflict. But lots of money is still being made. Africa works, for some people, even when fighting is continuing.
UN peacekeepers retain a presence in both countries
DR Congo and Sudan are so huge that several less distinct conflicts can take place in each nation at the same time.
United Nations peacekeepers are in both countries trying to help resolve their problems.
The UN has been barred by the Islamist government in Khartoum from deploying in Sudan's western Darfur region, but UN troops are in southern Sudan as they are across the vast expanse of DR Congo.
Since independence, both countries have had weak central governments which have failed to hold together the huge areas bequeathed to them by colonial powers, which themselves took little account of ethnic realities on the ground when they drew up their borders.
Today, the business investment the two countries attract is overwhelmingly aimed at exploiting and extracting raw materials.
In the case of Sudan it is crude oil, with Western, Chinese and other Asian companies cashing in - along with the Sudanese government.
DR Congo has most of the world's coltan, a mineral which is used in mobile phones.
There are also rich deposits of copper, gold and diamonds.
Mining has taken place despite the humanitarian disaster caused by the country's wars, and in many cases the grab for minerals has exacerbated the conflict.
DR Congo is so rich in natural resources - including huge hydroelectric potential from its rivers - that it could be an economic powerhouse for the whole of Africa.
But like its neighbour Sudan, it has been plagued by unstable government and war for most of the years since independence.
Despite the presence of UN soldiers in both countries, its thinly-stretched forces can achieve little without the political commitment of the governments in place, and in neither case do Sudan or DR Congo inspire confidence among UN diplomats.
Sudan's government came to power in a military coup in 1989.
Conflict is no stranger to DR Congo and Sudan
DR Congo's government is recently elected, following a UN-backed transition process.
But the choice that was given voters was essentially between the various warlords who brought the country to a standstill in the first place.
Maybe it would be wrong to expect too much economic development from countries which were born in such unfavourable circumstances.
The British seized Sudan as something of an afterthought to the more valuable territory of Egypt, and never really bothered to develop the southern black African-occupied regions of Sudan at all.
So it was no surprise that southern Sudan saw itself as quite separate, and fought a long war against the Arab-dominated north.
Hopes and fears
As for DR Congo, it was grabbed in the 19th century by the Belgian King Leopold as his personal fiefdom which he ran for profit - and was then run by Congolese who followed suit.
If you talk to people in Sudan or DR Congo it can be inspiring.
They have economic aspirations like anyone else, and are determined to make their own corner of Africa work.
But the bigger economic and political picture in Sudan and DR Congo, which is in turn partly a result of the two countries' histories, can still remain somewhat depressing.