One million staff who work in crowded places are to be trained in how to deal with terror attacks.
Police are aiming to get public limited companies which operate in busy areas such as city centres and sports and entertainment venues to teach their staff how to react in the case of an atrocity.
The move, unveiled today by Detective Chief Superintendent Scott Wilson at the Security and Counter Terrorism Expo, builds on an existing scheme where officers brief around 100,000 workers per year.
This extension of Project Griffin will instead see companies' existing trainers teaching colleagues.
Det Ch Supt Wilson said: "We need everyone to play a part in keeping the public alert, not alarmed. Police can help explain what the threats and risks to different sectors are, but companies are better placed to explain to staff exactly what action they can take to enhance their security and how to respond if the worst happens.
"Individual organisations have vital protective security information such as building layouts, security equipment and safety procedures. They have the local knowledge that could be vital to keeping staff and the public safe."
The Association of British Travel Agents is among businesses that have signed up to the project.
The move comes in the wake of the atrocities in Paris and Belgium, which saw attacks on "soft" targets with less security.
Plans are in place to boost the number of armed police nationally and counter-terrorism bosses have suggested the military could be drafted in to help in the wake of a large scale attack.
The initiative announced on Wednesday will target sectors including retail, hospitality, entertainment and travel, the National Police Chiefs' Council said.
Police have called on businesses that are interested in taking part to get in touch. They must be public limited companies and have a team of qualified trainers. Those in busy areas will be prioritised.
Security minister John Hayes said: "Everyone has a role to play in making sure we are alert to, but not alarmed by, the terrorist threat.
"This is a vital initiative which builds on the excellent work already undertaken through Project Griffin to ensure that employees are aware of the risk and best equipped to respond to an incident.
"Businesses have local knowledge which could be crucial in keeping people safe and it is absolutely right they receive this advice."