By Syed Shoaib Hasan
BBC News, Islamabad
Gen Kiani has a 'can-do' reputation
The rise of Gen Ashfaq Pervez Kayani through the ranks of the Pakistani military has been rapid if not extraordinary.
The man who succeeded Gen Musharraf as Pakistan's 14th army chief is noted for his patience, diligence, intelligence and sheer determination.
Another contributing factor has been his ability to keep a low profile when necessary while also being able to take decisive action when it's needed.
Gen Kayani's clan is one of the largest and most powerful in the northern Jhelum area of Pakistan's largest province, Punjab.
The harsh and arid region is famed throughout the subcontinent for only one product - soldiers.
So in many ways Gen Kayani was born to the job.
Passion for golf
He initially studied at the local cadet college in Jhelum, and was subsequently accepted at the army's military academy in the northern town of Kakul.
His father was also a soldier, a non-commissioned officer (equivalent to sergeant-major) in the Pakistan Army.
In August 1971 Ashfaq Kayani was commissioned as a second lieutenant, and joined the famed Baloch regiment.
The general is respected within the army
He joined up in time to experience the military defeat to India of the same year.
His first taste of politics came when he served as deputy military secretary to Benazir Bhutto in her first government in 1988.
Since then he has served at various levels of command.
He is a graduate of army colleges in Quetta and Islamabad, and General Staff College at Fort Leavenworth in the US.
Married with two children, Gen Kayani is president of the Pakistan Golf Association and an avid golfer.
He is respected in the army as a professional soldier who deliberately keeps a low profile.
This is in sharp contrast to the man he has been chosen to replace - Pervez Musharraf.
But maintaining a low profile has not meant that Gen Kayani has shied away from high-profile assignments.
He has a "can-do" image as a man who gets things done.
Gen Kayani has never been seen a part of President Musharraf's inner circle. But the president has always turned to him when the going gets tough.
It was Gen Kayani who oversaw the investigation into attempts to assassinate President Musharraf in December 2003.
As one of the army's senior most officers, Gen Kayani could confidently expect to take the top job
In his book, In the Line of Fire, President Musharraf writes how the investigations into the attacks initially ran into problems because of inter-agency rivalries.
"But these disappeared when I appointed Kayani in charge of investigations," the president wrote.
Observers believe that it was from this time onwards that Gen Musharraf started to rely heavily on Gen Kayani for crisis management.
But insiders say it was actually the winter of 2001-2002 that showcased Gen Kayani's abilities.
At that time he was serving as Director-General Military Operations (DGMO) - the army's operational commander.
As Pakistan's relations with India deteriorated, militants staged a deadly attack on the Indian parliament.
Delhi blamed it on the Pakistan-based militant group Lashkar-e-Taiba, and mobilised its army to take action. Soon the two nuclear-armed neighbours were dug in opposite each other along their 1,500km border.
Gen Musharraf has come to rely on Gen Kiani
Tempers were running high and a single aggressive movement could have sparked conflict. During this time, Maj Gen Ashfaq Kayani was in charge of all troop movements.
Insiders say it was his expert handling of the situation, and his constant contact with the Indian command that kept the eight-month stand-off from becoming an outright war.
It also brought him to the attention of Gen Musharraf. Subsequently, Gen Kayani was promoted to command the army's elite 10 Corps based in Rawalpindi.
When the attacks on President Musharraf took place in the city, Gen Kayani was the natural choice for the job of finding out who was behind them. The investigations led to a secret military tribunal convicting 11 men of planning and carrying out the attacks.
Soon after, he was made the head of Pakistan's powerful Inter-Services Intelligence (ISI) agency. In March 2007, he was part of the infamous "tribunal" of intelligence chiefs who met Chief Justice Iftikhar Chaudhry the day before his suspension by President Musharraf.
Gen Kiani in his younger days
He was later named as the only one who sat silently through the entire episode.
Gen Kayani was also the only official at the meeting who did not submit an affidavit against the chief justice.
President Musharraf's botched attempt to sack the judge triggered a political storm which led to deals with former prime ministers, Benazir Bhutto and Nawaz Sharif.
Gen Kayani was instrumental in making both these deals possible.
But while helping his "mentor", he has remained very much aloof from the increased political wrangling as elections approach.
As one of the army's most senior officers, Gen Kayani could confidently expect to take the top job. But because he was head of the controversial and shadowy ISI, some felt that he had disqualified himself from further promotion.
No ISI chief had ever been appointed commander of Pakistan's army. The agency's dealings have often been at odds with the policy of the government of the day.
Some observers also contended that Gen Kayani was too much "his own man" for Gen Musharraf to place faith in him.
But Pakistan's former dictator chose to ignore these and named Gen Kayani his successor in October 2007.
Since then, he has proven his mettle time and again, both in his roles as military commander and political arbiter.
He was instrumental in helping resolve the political stand-off between Nawaz Sharif and President Zardari early in 2009.
As head of the armed forces, he has spelled out a clear strategy to deal with the growing power of the Taliban.
Success in Swat has bolstered dwindling public opinion of the army, which plummeted to an all-time low during the last years of the Musharraf era.
Gen Kayani's greatest test, however, lies around the corner, as the army gears up to take on its biggest challenge yet by launching an operation in Waziristan.