The Director of Public Prosecutions is to step down from the role at the end of his five-year term of office in October, the Crown Prosecution Service has said.
Keir Starmer, who could have extended the term, said it had been "a huge privilege" to work in the role leading the CPS.
He said: "It has been a huge privilege to have led the CPS for the past four and half years. I have enjoyed my time very much and I look forward to continuing to work with my colleagues on the important work of the CPS until my term of office ends."
The Attorney General Dominic Grieve, praised Mr Starmer for bringing "humanity" to the role.
He said: "It has been a privilege and a pleasure to work with Keir. Not just a formidable lawyer, he has brought sound instinct and humanity to his role, noticeably in the guidelines he has published.
"He has led the CPS through a difficult time and leaves it as a more professional and more effective service than he found it. The CPS is now, more than ever, a key partner in the criminal justice system. In my view he has been one of the most successful directors of recent years."