The fight against the "invidious and devastating cancer" of racism, 20 years after the murder of Stephen Lawrence, must be continued, the Archbishop of York said on Saturday.
Dr John Sentamu, in his former role as Bishop of Stepney, played a major role in the campaign for justice alongside the Lawrence family and the inquiry into what went wrong.
The high-ranking cleric wrote in the Yorkshire Post how Mr Lawrence could now be a successful 38-year-old architect with a wife and family, loved and respected, had he not been victim of an unprovoked, racist murder by a gang of white youths in Eltham, south London on April 22 1993.
And while some progress has been made since then, the battle had not been won.
He wrote: "The elimination of racism remains a serious task for all of us.
"For racism is like an invidious and devastating cancer in society, attacking community structures and all its component
"We may congratulate ourselves that it has been eradicated in one place and we can relax, but sadly it often turns up somewhere else, with slightly different characteristics - this time perhaps focused on asylum seekers, or eastern European workers.
"Wherever it is found it must be fought."
Dr Sentamu said the murder "reverberated through many lives, causing pain which cannot be calculated, this side of the grave".
He said: "As we remember Stephen's death at this time we need to renew our determination to rid our communities of racism, hatred, fear, ignorance, stereotyping, and the advantaging or disadvantaging of others because of their colour or ethnic origin."
There has been progress in these 20 years, the Archbishop said, "away from the ignorance, fear of difference and stereotyping, which were hallmarks of that crime and its investigation at the time".
That came due to the determination and courage of Mr Lawrence's parents Neville and Doreen who fought "tirelessly" to bring about justice.
Dr Sentamu said: "For the first four years their fight seemed to be doomed to disappointment. "First, the police failed to respond promptly, with clear determination, to the information received from the public, giving names of suspects.
"This led to the disappearance of scientific forensic evidence, so that the investigation was inconclusive, and charges against five arrested suspects were dropped.
"They even failed to take up the floorboards when they received information that knives were hidden below. Early arrests would have yielded incriminating evidence."
A subsequent private prosecution ended with the charges against two suspects being dropped and the acquittal of three others.
When the then Home Secretary Jack Straw called for a public inquiry, Dr Sentamu was called to be an adviser, as he was then Bishop of Stepney and had been a High Court Advocate in Uganda.
The Archbishop wrote: "In the course of the hearings it became clear that the Lawrence family had been ill-served by our justice system.
"The 'canteen and occupational culture' of The Metropolitan Police Service had resulted in what the Inquiry described as 'institutional racism', a concept which was clearly discernible in the investigation of the murder of Stephen Lawrence.
"Namely, 'the collective failure of an organisation to provide appropriate and professional service to people because of their colour, culture, or ethnic origin'.
"It can be seen or detected in processes, attitudes and behaviour which amount to discrimination through unwitting prejudice, ignorance, thoughtlessness, and racist stereotyping which disadvantage minority ethnic people."
The report made 72 recommendations which led to police forces and many other public and private organisations, including the Church of England, to improve practices.
The case also led to a major legal change, the end of the double jeopardy rule, which meant murder cases could be re-tried if fresh evidence came to light.
Dr Sentamu said: "Everyone will now be aware that the implementation of this recommendation has resulted in the retrial and conviction of Gary Dobson who was 'acquitted' in the private prosecution, and of David Norris whose charge had been dropped in the same prosecution.
"The force of justice may be slow, but it is sure."