John Lawson, head of pensions policy at Standard Life, is to join rival Aviva in the New Year as head of policy, corporate benefits.
Lawson had been in his current role for more than 11 years but has now left the company to take a break before joining Aviva in January.
A decision to replace Lawson at Standard Life has not yet been taken.
Lawson will report to Graham Boffey, managing director of Aviva's corporate benefits business.
"Boffey said: "I'm delighted that John is joining the team at a time when our workplace business is gaining significant momentum. [He] will use his industry expertise and insight to further shape our end-to-end corporate business, and to ensure we get it right for our customers."
Standard Life said Lawson leaves with its best wishes.
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