Commander Jim Stokley - who leads the Met's response to gang crime - talks about the ongoing work to manage the threats posed by gang violence.
"This year violent crime, and its fatal consequences, has often been in the headlines for very real and sadly obvious reasons. The statistics speak for themselves - 11 young men aged 25 and under have been murdered so far in 2018. But those statistics represent young people - much loved sons, brothers, friends. We must never forget the human tragedy and cost.
"Broadly speaking, half of all gun crime is linked to gangs and around 20% of knife crime is too.
"The gang violence matrix is an intelligence tool that the Met uses to understand the threat of violence posed by gangs and also importantly to gang members. It really can save lives.
"We build a picture based on intelligence - from police, our partner agencies, and from Londoners - our communities. The matrix is then used to target activity to reduce the risks of violence posed by or threatened against our young people. That can be any number of things from diversion schemes, including help with employment, to enforcement activity.
"I know that some people have been critical of the matrix and that is why it's important that we take every opportunity we can to explain what it is, and what it isn't. In the aftermath of the London riots of 2011, the Met realised that we did not understand as we should have which of London's young people were in gangs and which areas of London they were linked to.
"Since then we invested a lot of time in understanding who is likely to be a victim, or aggressor, or both.
"We use a very strict criteria - the threshold for including a person on the matrix is high; only where we have at least two corroborated pieces of tested intelligence are people included. Inclusion is kept under constant review and whilst about 3,500 people are currently included, since 2012 over 4,000 people have been removed.
"This is often for very positive reasons: they have left the gang lifestyle; been successfully diverted from crime.
In some cases, where we have the right level of evidence, they have been deported. But sadly there will be some who have died, including being murdered.
"The Met is determined that we will play our part in making sure our young people know they have choices, they can get support to turn away from gangs, that our intelligence is for their protection from harm as equally as it is for enforcement. What we want is to do all we can to stop young people from joining a gang in the first place. Londoners can help us - we all have a part to play. If you know of a youngster at risk of being drawn into a gang, or who is already part of one, please tell us."