James Bullion has been acting in the role of interim chief executive during Terroni's recent leave of absence and will continue to act in this role until Sir Julian Hartley takes up post as CQC's permanent chief executive.

Until her departure from CQC, Terroni will be working directly with the chair Ian Dilks to plan for the arrival of Sir Julian.

Terroni said: 'At the beginning of September, I informed the chair of my decision to not apply for the permanent chief executive role, as I recognised the need for fresh leadership to take us forward.

'It has been a huge privilege to act as interim chief executive, but it has also been an intensely challenging experience, and I needed to take some time away to absorb the impact it has had on me. This led me to think about what comes next – my career has been non-stop for the last 22 years, driven by the desire to make a difference for people who use services, but I now want to take some time to think about what the next 22 years could look like.

'I wish Julian all the best as he takes on this very special job. He is a well-respected and experienced leader within the health and social care sector, and I know that under his leadership and with the support of you all, CQC will make the necessary improvements to get back on track.

'I am proud to have been part of CQC and I have every confidence that with the wonderful people in this organisation, we will come back stronger than ever and better able to help ensure that people get good, safe care.'

Dilks said: ‘I want to thank Kate for her enormous contribution to CQC, as chief inspector of adult social care, as deputy chief executive and most recently as interim chief executive.

‘She took up this last role at a particularly challenging time for the organisation. Her openness in acknowledging that we needed radical improvement – and the plans she started to put in place to make this happen – helped lay foundations for the work we have ahead of us to respond to the Dash review and Sir Mike Richards' report and to rebuild trust with the public, providers and our staff.

‘While she has stepped down as interim chief executive, I am pleased that she will be working with me to plan for the arrival of Sir Julian Hartley as CQC's permanent chief executive. Her knowledge of the organisation and commitment to ensuring that we can once again deliver on our core purpose will be invaluable to this work..