Questions over Britain's security have come to the forefront of the election after the UK suffered its third terror attack within months.
Here is what the three main parties are pledging if they take power on June 8.
The Conservatives have pledged to create a new Commission for Countering Extremism that will have a remit to clamp down on "unacceptable cultural norms" such as female genital mutilation.
They have also said they will invest £178 billion in new military equipment over the next decade and maintain the Trident nuclear defence to "to provide the ultimate guarantee of our security".
Work will continue on a £1.9 billion investment in cyber security against online attacks, the party said.
And by leaving the EU, Britain will be able to take control of immigration policy "for the first time in decades", it said.
Labour have pledged a slew of funding for police and security agencies.
They would hire 10,000 more police officers to work in communities, plus 3,000 more firefighters and 3,000 more prison officers.
The party has promised to bring in 1,000 more staff at security and intelligence agencies MI5, MI6 and GCHQ to step up efforts to prevent terrorism.
It will also recruit an additional 500 border guards.
Labour supports the renewal of the Trident nuclear deterrent, though Jeremy Corbyn said he would never want the UK to launch the first nuclear attack in a conflict.
- Liberal Democrats
The Liberal Democrats would give an extra £300 million a year to police forces and would also place a strong focus on cross-border intelligence with international partners.
They would allow intercepts where justified and permit surveillance of those suspected of serious crime and terrorism, but would roll back state surveillance powers and state-sponsored efforts to break online encryption.
A Lib Dem government would scrap the "flawed" Prevent anti-extremism scheme and replace it with a new scheme that engages communities.
The party is committed to remaining in Europe, meaning the UK would remain open to EU citizens, but says they would control borders with stringent entry and exit checks.
It supports maintaining Trident but has pledged to reduce the level of Britain's nuclear fleet.
- The SNP
The SNP have said that police numbers are up in Scotland - in contrast to England - while crime is at a 42-year low.
Their manifesto pledges focus more on defence.
The party has said it would scrap Trident, and spend the billions in savings on public services.
However they would instead press for investment in conventional defence, including at HMNB Faslane as a conventional military base.
SNP MPs would support a Strategic Defence and Security Review to assess if ocean-going patrol vessels should be permanently based in Scotland.
They might also lobby for more aircraft to protect the country's skies.
- Green Party
The Green Party has made few pledges on the issue of security.
It would create a UK-wide strategy to tackle gender based violence, including domestic violence, rape and sexual abuse, FGM and trafficking.
It has pledged to cancel the planned Trident replacement, which it says would save at least £110 billion over the next 30 years.
The party has pledged to be tough on crime, with a promise to hire an additional 20,000 more police and employ 7,000 more prison officers.
Ukip has also vowed to reinstate stop and search and crack down and would ban the burka or other face covering in public.
It would create an over-arching role of Director of National Intelligence, who will be lead a new, single, unified intelligence service.
The party has also pledged tougher action on so-called honour crimes, grooming, and forced marriage.
Ukip has said that it would retain the Trident nuclear deterrent.