The new Prime Minister needs to be ready to shift gear from campaigning to governing

The two final contenders for the leadership of the Conservative Party are campaigning across the country, with Jeremy Hunt and Boris Johnson relentlessly appealing to the party membership as they attempt to secure their votes.

But winning a Conservative leadership contest is a very different challenge to being prime minister. When not running their campaigns, both contenders need to be thinking about running the government.

The new Prime Minister needs to have a vision

Because the leadership debate has mainly focused on the personalities of the two men, neither has offered much clarity on how they intend to resolve the Brexit impasse, beyond commiting to leaving the EU by 31 October. But they haven't said how they intend to do this with Parliament resolving to stop no deal and the EU refusing to re-open the Withdrawal Agreement.

Meanwhile, important issues such as tax and public spending have barely featured in the debate. Neither contender has set out a substantial domestic agenda or a clear mission for government. As David Cameron’s Deputy Chief of Staff Baroness Kate Fall says the glue of sorting out the public finances was crucial in holding the Coalition government together. Without a clear unifying vision for their administration, Johnson or Hunt will struggle to unite the party – and country – for long.

A Prime Minister is only as good as their team

One of the priorities for an incoming prime minister is to ensure that they have a good team with clear roles and responsibilities. The first job will be to appoint their Cabinet and fill the junior ministerial ranks. The Prime Minister will need to adapt as key campaign allies are dispersed across Whitehall. They will need to appoint ministerial teams who can work together. And they will have to manage disgruntled former ministers who are returned to the backbenches. They should also start thinking about who they are bringing into No10, who (if anyone) they will keep from Theresa May’s team and how their appointees will work with the permanent civil servants.

The nature of this transition of power – a relatively quick internal party debate, rather than a longer, national contest that allows time for planning – means that there is a risk that the contenders do not think ahead to build their top team. Making the right staffing decisions early on – the ‘high octane HR’ of the first few days of a new administration – is crucial to setting the tone for the new PM's tenure.

The Prime Minister must know when to delegate 

The next PM cannot take a ‘hands-off’, chairman-like approach that sees Secretaries of State and political staff do the hard work of governing. Sir Mark Lyall Grant, former National Security Advisor, says that a PM can expect to be taking up to 40 decisions a day across all areas of government policy.

The ability to take difficult decisions was one of the key attributes of a good prime minister which Sir Mark and Baroness Fall identifed. And over the course of an administration, more and more decisions tend to get sucked into No10. As David Cameron found out in the case of Andrew Lansley’s NHS reforms, giving your Secretaries of State a long leash can lead to political problems down the line – a prime minister cannot stay above the fray for long.

As well as making decisions on the strategic priorities of government, a good prime minister needs to ensure that those decisions are put into practice. There are existing structures that allow No10 to keep tabs on policy implementation – the prime minister needs to use them to hold ministers and officials to account for their commitments.

The next Prime Minister will face the same issues as his predecessor

Theresa May’s premiership was bedevilled by a lack of party agreement on what Brexit should mean and by the challenges of a minority government. Her successor will inherit exactly the same situation, and Brexit will be the defining issue of the next premiership (and probably several after that).

Over the next few weeks both Johnson and Hunt will bask in the adulation of the party faithful and compete for short-term headlines. It will be an intense and exhausting experience, but they need to think long-term and beyond the contest. Without a clear sense of what they want to achieve, how they intend to achieve it and who they will trust to work with them, the next Prime Minister will be quickly confronted by the painful reality of trying to run a divided country without a proper plan.

They won’t have time to think about this after inheriting the keys to 10 Downing Street. They need to do so now.