Before coming to power, Margaret Thatcher paid a visit to Yugoslavia, where she had a meeting with President Tito. The conversation turned to China, where Chairman Mao's widow had recently been stirring up trouble for the leadership. Tito remarked that he disapproved of women interfering in politics. "I don't interfere in politics, " declared his guest, eyes ablazing, "I AM politics."

Therein can be found both the secret of Margaret Thatcher's success and the seeds of her downfall. Her supreme confidence helped overcome widespread doubts that a woman could lead her party and her country, but in the end her arrogance alienated the very people she needed to retain power.

Thatcher's story presents a unique challenge to political biographers, largely because her overpowering personality and strident views make a fair assessment difficult to achieve. The writer has to tread a fine line between hagiography and demolition job. Happily, John Campbell's book manages to avoid these pitfalls, and his account of Thatcher's life and times is even-handed, thorough and highly readable. The first volume of Campbell's biography -- The Grocer's Daughter -- covered Thatcher's early life and career, concluding with her arrival on the threshold of Number Ten. Margaret Thatcher, Volume II: The Iron Lady concentrates on her entire eleven-and-a-half years as mistress of Downing Street, as well as the aftermath of her removal from power.

The first thing to say is that it's a huge read - over 800 pages. But this is no more than the subject deserves, given Thatcher's dominance, not only in her role as Prime Minister, but also as an inveterate meddler in the work of her ministers. From health and education to local government finance and foreign affairs, there was barely an aspect of policy which Margaret Thatcher did not seek to influence.

All the important events of her premiership are there - the three election victories, the Falkands, Westland, the miners' strike, the Poll Tax, and her dramatic departure at the hands of her own party. But the book goes beyond the big stories to put her premiership in a wider context. Take housing: Campbell shows that Thatcher's policy of encouraging council tenants to buy their own homes, while prohibiting local authorities from building new houses with the proceeds, led to a massive shortage of affordable housing, and by extension to large numbers of homeless people on British streets.