Dozens of new mental health centres are set to open in libraries, banks and other high street spots across London.
The Government said the plan will help stop those in crisis waiting months for help.
Officials also announced that more people in needing mental health support will be given specialist care in dedicated emergency departments, rather than waiting in busy A&Es.
In the capital, 30 hubs are planned at new and existing sites, plus another one in Luton that will be run by the East London NHS Foundation Trust.
Community-based mental health centres will open in high streets in Wandsworth, Croydon, Lambeth, Newham, Southwark, Hackney, Barking and Dagenham, Waltham Forest, Enfield, Islington, Camden, Barnet, Hammersmith and Fulham, Westminster, Barnet and Brent.
Another four are planned for areas of south west London and one in central London.
Nine new mental health emergency departments will open at London hospitals, while one will set up in Luton.
Prime Minister Andy Burnham said that the locations will be a “lifeline” for the thousands of people.
Across the country there will be 100 new community mental health centres and 59 dedicated mental health emergency departments in the “biggest redesign of mental health services in a generation”, the Department of Health and Social Care said.
The centres will offer walk-in support where people can attend without being referred.
Health and Social Care Secretary Yvette Cooper said: "Too many people are only getting mental health support when they reach crisis point, after struggling for far too long to get the help they need.
"These new community mental health centres will help people get support earlier and closer to home, making it easier to get the right care before problems escalate.
“And when someone does need urgent help, new mental health emergency departments will be able to make sure they are seen quickly by specialist teams in the right setting.
"This is how we can turn the tide on mental ill health - preventing more people from reaching crisis, cutting waits for care, and building an NHS which is there for everyone when they need it.”
The new mental health emergency departments
Lakeside Mental Health Unit
West London NHS Trust
Existing site
Northwick Park And St Mark's
London North West University Healthcare NHS Trust
Existing site
Whipps Cross University Hospital
Barts Health NHS Trust
Existing site
Newham General Hospital
Barts Health NHS Trust
Existing site
City & Hackney
East London NHS Foundation Trust
Existing site
The Royal London
Barts Health NHS Trust
Existing site
Calnwood Court, Luton
East London NHS Foundation Trust
Existing site
Maudsley Hospital near King's College Hospital
South London And Maudsley NHS Foundation Trust
Existing site
Queen Mary's Hospital, Bexley
Oxleas NHS Foundation Trust
Existing site
St George's Hospital, Wandsworth
South West London And St George's Mental Health NHS Trust
New site