As well as fighting the insurgency in Afghanistan, Gen Richards will have to battle for resources for the Army at a time of increasing financial strain.
BBC defence correspondent Caroline Wyatt said Gen Richards is seen as "astute" and a "good communicator".
As former head of the International Security and Assistance Force, he has first-hand experience of Afghanistan.
Our correspondent said: "General Sir David Richards is seen as a good communicator who is also politically astute, and perhaps more likely to fight his battles behind closed doors."
Gen Sir David Richards
Gen Richards has extensive operational experience in East Timor, Sierra Leone, and first-hand knowledge of the challenges in Afghanistan, gained as commander of Nato coalition forces there between 2006 and 2007.
Asked earlier this month if he would be presenting a "shopping list" for military equipment on his first day in office, Gen Richards answered: "I will not.
"It is impossible to say whether having more equipment of a particular kind would lead to less casualties, and pretty fruitless speculating about it," he said in an interview with the Times newspaper.
"The enemy's tactics will always reflect, and try to exploit, how we operate - my American comrades first taught me the adage, 'the enemy has a vote' - and our own tactics must reflect the equipment and troop numbers we have.
"It is a truism to state that the more we have, the more we can do."
Published: 2009/08/28 01:18:49 GMT
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