Prime Minister David Cameron has welcomed Conservative predecessor Baroness Thatcher back to 10 Downing Street for a reception in her honour.
They shook hands and waved at photographers before entering the building but did not answer questions.
A smiling Mr Cameron said: "It's good to have her back here."
Baroness Thatcher, 84, is one of the first guests to be hosted in Downing Street since the coalition entered office last month.
She wore a light blue dress and coat for her meeting with Mr Cameron, emerging from Number 10 some 45 minutes after going into the building.
Labour's Gordon Brown also hosted her in Downing Street after taking office in 2007.
In 2005 Baroness Thatcher, prime minister from 1979 until 1990, was advised by doctors that she should not make public speeches in the wake of some minor strokes.
She became the first living prime minister to be honoured with a statue in the House of Commons in 2007.
Baroness Thatcher was last in 10 Downing Street in November last year when she attended the unveiling of her portrait.