Thousands of delegates have arrived in Birmingham for the first day of the annual Tory party conference.
A ring of steel is in place around the International Convention Centre, with a heavy police presence in the area and a number of road closures.
The eleven thousand delegates have packed into the city's hotel rooms and guest houses but against the back-drop of these austere times there will probably be more debate and analysis than partying in the days to come.
One significant absentee is the Sutton Coldfield MP and Chief Whip Andrew Mitchell. Following the continuing row over allegations that he called police guarding Downing Street 'plebs', he does not want to be a distraction as the events unfold.
A further headache for Mr Cameron to overcome over the next few days is the suggestion that his grip on power is weakening in the wake of the collapse of the rail franchise settlement for the West Coast mainline contract.
Some of his own MPs are asking for other Department for Transport contracts to be re-examined in the wake of what Labour describe as the 'shambles' of errors and miscalculations uncovered in the debacle.
Among those likely to press their case this week as the delegates file into the ICC will be campaigners opposed to High Speed Rail. They have taken courage from the admission over West Coast mainline and believe that it strengthens their case.
The Conservative health team will be defending the NHS shake-up. Broxtowe MP Anna Soubry is the new Midlands face on the ministerial team.
All well aware that this conference will attempt to reassure voters the country is being led out of its economic woes.
David Cameron will make his keynote speech aware that many warm words were written last week about Ed Milband's address in Manchester.
He will be hoping to reassert his authority but he is bound to point out that being in government is often tougher than being out of government.