Liberal Democrats have outlined the six red lines that must be agreed to as part of any coalition negotiations in the next government.
The red lines cover education, the economy, tax, health, public sector pay and the environment:
1. Protecting education funding
Liberal Democrats want to protect per pupil funding from nursery to 19, in real terms, by the end of the parliament.
This would amount to £5.2bn more funding than is planned by the Conservatives and £2.5bn more than Labour.
2. Introduce a 'stability budget' in the first 50 days
A stability budget would set out the next government's commitment to balancing the books in full and fairly.
It would also give a clear commitment to investing in our public services, including schools and hospitals.
3. Increasing the personal tax allowance to £12,500
Liberal Democrats have already delivered an £825 tax cut to millions of workers.
The next parliament must make significant progress to getting to the £12,500 threshold in its first year by increasing the allowance to £11,000 by April 2016.
4. Invest £8bn a year by 2020 in the NHS
The Conservatives have failed out how they would meet the NHS funding gap, and Labour's plans fall short by almost £4bn.
Liberal Democrats would insist that the next government give the NHS the money it needs as well as introduce maximum waiting times across mental health services.
5. Pay rises for public sector workers
Public sector workers have played an important role in helping get the economy on track and Liberal Democrats want to give them the pay guarantee they need.
We would introduce a minimum pay increase in line with inflation for the next two years, and guarantee real terms increases in pay once the books have been balanced.
6. Fight climate change and protect nature
Liberal Democrats want to introduce five green laws that will include radical targets to zero carbon energy, discounts for energy-efficient homes, a pledge to improve air quality and a plan to investment in green forms of transport, such as cycling.