"I have been so very impressed by what I have seen and heard," said Baroness O'Loan at Southwark's cohesion and engagement showcase event at Tate Modern on Wednesday.
"I want to congratulate the people of Southwark on what has been achieved. I think it's quite exceptional."
Baroness O'Loan, Northern Ireland's first Police Ombudsman, was speaking at the Shining Lights event at Tate Modern marking Southwark Council's Beacon Authority award for commitment to community engagement and partnership working.
"For me community cohesion is about the recognition and accommodation of people's rights and the existence within a community of full respect of the culture of all its members."
Cllr Adele Morris, Southwark's executive member for communities, equalities and citizenship, opened her address by saying that she had lived for thirty years in the same flat where she had brought up her family.
"I love Southwark. It's a borough of great diversity," added Cllr Morris who said that the population stood at about 279,000.
"We have constantly changing communities. The population churn is around 25 per cent which is very high so we have people coming and moving out.
"We are the largest social landlord in London. We have over 40,000 tenant properties. 37 per cent of our households are one person. We have social housing and very luxurious housing along the river.
"Jobseeker allowance claiment rate is higher than the national average but people who do work have a higher salary than the national average.
"I have worked in the community," said Cllr Morris recalling her earlier years in the area before being elected. "I have always had an interest in people. That is really what communities are: individuals being part of a group; groups being part of a community and those communites being Southwark. It is really important that we get on."
Earlier Synthia Griffin, Tate Modern's regeneration and community partnerships curator, welcomed the conference delegates to "Southwark's premier venue".
"It's ten years since Tate Modern opened its doors in Southwark. As you may know it's now the most visited museum of modern art in the world. We welcome over five million visitors a year.
"We are actively involved in the everyday life of the local community that is Bankside and Southwark. Partnership is central to this."
BBC London presenter and Southwark resident Jumoke Fashola chaired the day long event attended by community group representatives and residents.
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