When the grandmother of Russia's human rights movement first met Putin in November 2002, she was impressed by his humility and willingness to listen to activists like herself after less than three years as president.
By the time they met again in December 2006, Putin was riding high and walking with a swagger after on an oil-fuelled economic boom that made him hugely popular in Russia. He was, she said, no longer listening.
"He was a different man, a caricature of himself. I took one look and wanted to leave the room," said Alexeyeva, who has been challenging the authorities over human rights since the start of the Soviet dissident movement in the 1960s and is still a force to be reckoned with at the age of 84.
"Putin came to believe that everyone wants him to stay in power ... He doesn't understand. It's a terrible thing to have power. Very few people can handle it properly," she said in an interview in her light central Moscow apartment.
Alexeyeva, who met Putin in her role as a member of the presidential human rights council, decided not to walk out of the room on that occasion.
She also resisted the temptation to show her disdain for the former KGB spy by quitting the advisory council, because doing so might limit her ability to defend human rights.
But nearly six years later, Putin is back as president after four years as prime minister and her patience has snapped. She resigned from the council last week, saying Kremlin interference in the choice of new members made its work pointless.
Alexeyeva was the 14th representative of the 40-member council to resign since Putin won a new six-year term in March, and the highest-profile defector.
Putin shows no sign of concern that it was his return to the Kremlin that prompted the resignations, which have put the spotlight on Russia's poor human rights record. But Alexeyeva is not surprised and thinks his days in power are numbered.
"Putin would like Russia to be like the Soviet Union," she said. "But he can't do it. Twenty years have passed since the collapse of the Soviet Union. Things are different now."
Alexeyeva and a small group of like-minded people began monitoring human rights in the Soviet Union nearly half a century ago. A decade later she helped found the Moscow Helsinki Group to check the Soviet Union's compliance with international human rights conventions.
"I had to do something. I saw that life could be better," she said, explaining why she put her own freedom at risk to draw attention to the plight of Soviet dissidents, a decision that led to her expulsion from the Soviet Communist Party.
She is now white-haired and frail, and at times struggles for breath as she speaks, but the constant interruptions of telephone calls from colleagues bear witness to the active role she still plays as a rights campaigner.
Russia's human rights record is far from perfect - a reminder of this is a book displayed prominently on a shelf in her living room. It contains work by Anna Politkovskaya and was published after the campaigning journalist was shot dead outside her Moscow apartment in 2006.
The opposition says there are still political prisoners in Russia - a charge the Kremlin denies - and problems include homophobia, violence against women, sexism and xenophobia.
But Alexeyeva does not like to hear comparisons with the dictatorship of Josef Stalin or even his less repressive Soviet successors, Nikita Khrushchev, and Leonid Brezhnev.
"I was 25 when Stalin died. I remember what it was like to live in a totalitarian state. Then came Khrushchev and Brezhnev. You can't make comparisons with then. I still don't like it much but it's better now," she said.
Journalists can freely call her to set up interviews. When Western journalists first took an interest in her, her phone was bugged and they risked being stopped on the way or the KGB would detain her before they reached her apartment.
She dismisses the comparisons that have been made between police raids this month on the homes of the organisers of the biggest protests against Putin since he rose to power in 2000, and Stalin's purges of the 1930s, when a knock on the door could presage a death sentence or years in a labour camp in Siberia.
"People are saying it's like 1936 but that is not true. Life is much more free now," Alexeyeva said.
She said such intimidation, and big fines for protesters who step out of line, would not deter the opposition.
"It's the beginning of the end. I think he (Putin) has two years more (in power)," she said, predicting that he would not be able to stifle the protest movement because "once the toothpaste is out of the tube you can't put it back."
Alexeyeva celebrates her 85th birthday on July 20. When she celebrated her 75th, she made a toast saying it was the happiest time of her life. Since then, a civil society has emerged and the anti-Putin protests have taken off in big cities, although not in the vast provinces.
Smiling as she looked ahead to her birthday, she said: "I could make the same toast again now."
Alexeyeva's frailty belies the toughness and determination that has set her apart from other human rights activists. She cannot attend protests now because her legs are weak, but she follows them on television and the Internet.
Until recently she took part in rallies on the last day of months with 31 days in defence of Article 31 of the Russian constitution on the freedom of assembly.
At times she chuckles as she recalls her frequent brushes with the authorities over the decades. She has never served a jail term but has been detained, called in for questioning and had her apartment searched too many times to remember them all.
In a typical act of defiance, she would sometimes taunt her KGB foes by pulling goodies from her bag such as an orange, fresh ham or even an eclair during questioning.
"The smell got to them. They didn't know what to say," she said. Then she added: "Not once in all those years did I ever say anything that could have been used against anyone else."
Alexeyeva and her husband were forced to flee the Soviet Union in 1977 when it got too tough. But she continued her human rights work from abroad and was able to return in 1990 after Soviet leader Mikhail Gorbachev's "perestroika" reforms.
She believes Russians are better prepared now for democratic change than when the Soviet Union collapsed in 1991, and that it will be possible to avoid bloodshed if Putin goes; but the stakes are high.
"If we for some reason miss this chance now, we will fall back into the Third World," she said.