By taking command in person in Natal, Buller had allowed the overall direction of the war to drift.

Because of concerns about his performance and negative reports from the field, he is replaced as Commander in Chief by Field Marshal Lord Roberts.

Roberts quickly assembles an entirely new team for headquarters staff and he has chosen military men from far and wide: Lord Kitchener (Chief of Staff) from the Sudan; Frederick Russell Burnham (Chief of Scouts), the American scout, from the Klondike; George Henderson from the Staff College; and Neville Bowles Chamberlain from Afghanistan.

Like Buller, Roberts had first intended to attack directly along the Cape Town–Pretoria railway but, again like Buller, had been forced to relieve the beleaguered garrisons. 

Leaving Buller in command in Natal, Roberts masses his main force near the Orange River and along the Western Railway behind Methuen's force at the Modder River, and prepares to make a wide outflanking move to relieve Kimberley.

Except in Natal, the war has stagnated. 

Other than a single attempt to storm Ladysmith, the Boers have made no attempt to capture the besieged towns.

In the Cape Midlands, the Boers had not exploited the British defeat at Stormberg, and have been prevented from capturing the railway junction at Colesberg.

In the dry summer, the grazing on the veld becomes parched, weakening the Boers' horses and draft oxen, and many Boer families join their menfolk in the siege lines and laagers (encampments), fatally encumbering Cronjé's army.

Roberts launches his main attack on February 10, 1900, and although hampered by a long supply route, manages to outflank the Boers defending Magersfontein. 

A cavalry division under Major General John French launches a major attack to relieve Kimberley on14 February 14.

Although encountering severe fire, a massed cavalry charge splits the Boer defenses on February 15, opening the way for French to enter Kimberley in the evening, ending its one hundred and twenty-four days' siege.

Meanwhile, Roberts pursues Piet Cronjé's seven thousand-strong force, which has abandoned Magersfontein to head for Bloemfontein.

General French's cavalry is ordered to assist in the pursuit by embarking on an epic fifty kilometer (thirty-one mile) drive towards Paardeberg where Cronjé is attempting to cross the Modder River.

A pincer movement involving both French's cavalry and the main British force, attempts to take the entrenched position on February 17 a but the frontal attacks are uncoordinated and so are repulsed by the Boers.

Finally, Roberts resorts to bombarding Cronjé into submission.

In Natal, the Battle of the Tugela Heights, which started on February 14, is Buller's fourth attempt to relieve Ladysmith.

The losses Buller's troops have sustained persuades Buller to adopt Boer tactics.

Despite reinforcements, his progress has been painfully slow against stiff opposition.

However, on February 26, after much deliberation, Buller uses all his forces in one all-out attack for the first time and at last succeeds in forcing a crossing of the Tugela to defeat Botha's outnumbered forces north of Colenso. 

Roberts now surrounds General Piet Cronjé's retreating Boer army.

It takes ten days to bombard the Boers into submission, and when the British troops use the polluted Modder River as water supply, typhoid kills many troops.

General Cronjé is forced to capitulate at Surrender Hill with four thousand men on February 27.

The Relief of Ladysmith is effected the day after Cronjé surrenders, after a siege lasting 118 days, but at a total cost of seven thousand British casualties.

Buller's troops march into Ladysmith on February 28.