David Cameron - the first Conservative leader to win an outright majority for 23 years - named his ministerial team.
Sajid Javid took the job of Business Secretary and Boris Johnson was handed a non-ministerial role while he remains Mayor of London.
A number of female MPs, including Priti Patel and Amber Rudd, were also promoted to leading positions.
Harriet Harman is stepping down as Labour's deputy leader, she has announced.
She paid tribute to Ed Miliband "for his leadership" and "for his decency, his commitment and his constant striving for a fairer country".
In a speech, she said: "On the resignation of Ed Miliband as leader of the Labour Party I, as his deputy, am stepping forward to be acting leader until a new leader is elected by the party."
She added: "With a new leadership team in place, after what has undoubtedly been a serious defeat, the Labour Party will be best placed to be the strong opposition this country needs - defending our NHS and our public services, and fighting for fairness, equality and social justice.
"That determination will be all the fiercer in the face of this Tory government."
It was one of the last big Cabinet jobs to be announced but the Prime Minister has chosen to stick with Jeremy Hunt as Health Secretary.
Prime Minister David Cameron has today continued to put together his new cabinet. Here is what the new-look cabinet looks like so far.
David Cameron was unsurprisingly in a great mood as he spoke to journalists before addressing his 331 Conservative MPs today.