Government Digital Service (GDS) executive director Mike Bracken is leaving the government to join the Co-operative Group as chief digital officer.
Bracken revealed on his blog earlier this week that he was leaving his post at GDS and his role as the government's first chief data officer, but did not reveal his destination.
However, Bracken said on Twitter that he has started following the Co-op account and directed people to his blog where he announced his move to join the UK retail and services group.
Bracken will report to Co-op chief executive Richard Pennycook, and will use his new position to help other governments and civil organisations adopt digital technologies and strategies.
"I have loved my time in government, and will be so sad to leave my friends at GDS and in the digital, technology and data professions," he wrote.
"Yet I've been involved in the intersection of government, the internet and social change for 20 years, so leaving my current role means I am leaving Whitehall and the mandarins, not the wider community.
"With Richard's support, I will be able to advise and help international governments and those in the emerging digital government and civic tech movements."
Bracken described the Co-op's collaborative values and ethics as close to his heart, and said that there are parallels between the organisation and government.
The new job will give Bracken the "opportunity to work at scale, in a £10bn organisation, to set a digital strategy and improve member experience, to work with inspiring colleagues all over the country, and to build strong businesses serving diverse audiences".
Bracken made his decision to leave government known to John Manzoni, chief executive of the Civil Service, last Friday, and will resign from his posts on 30 September.
"At the end of last week I went to see my boss, John Manzoni to tell him I'm leaving government," Bracken said.
Manzoni thanked Bracken for his time in the Civil Service, and praised him for the role he played at GDS.
"Mike has played a central part in developing a functional model at the heart of government, and digital has paved the way for joining up the centre and departments into a single vision," he said. "I wish him the best for the next phase of his career."
The departure appears to be unexpected, given that Bracken was appointed as the government's chief data officer in March. This means that Bracken will leave two senior government posts that will need to be filled in the autumn.
GDS project leader Neil Williams said on Twitter that he was shocked by Bracken's departure and called it the end of an era.
In shock. End of an era. But not the end of digital transformation of government. Not by a long chalk.— Neil Williams (@neillyneil) August 3, 2015
Bracken did not shed any light on why he was leaving government or where he is going next, although he said that more will be revealed on his personal blog.
This leaves the subject open to speculation, and could prompt questions as to what sparked his decision to leave and whether it is an indication of GDS failing to succeed with its mission to push the adoption of digital technology and services in government.
However, Bracken is confident of GDS' future. "I'm leaving the government's digital delivery in capable hands, especially with the support we are getting for the future of digital transformation from the new minister for the Cabinet Office, Matt Hancock," he said.
"The GDS leadership is strong, our plans are clear and focused, our people - and digital teams across government - are rolling up their sleeves to continue the work of transformation."
Bracken was instrumental in the creation of GDS in April 2011, and the service now has an influential role in government, including with the government-as-a-platform plans to streamline the creation of public sector services.
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