However, the early stages of creating the OMD group have been completed and Manning describes himself as an "architect" who is most inspired by creating a business. So there seems an element here of job well done but now is the time to hand the reins to someone fresher and more energised by the day-to-day affairs.
Step forward Steve Williams, a wily veteran who has been with OMD UK (and, before it, BMP's media department) man and boy. Williams brings solid, hard-working values to the OMD template and is well liked internally.
But what of Manning? His departure next year will bring to an end a 20-year working relationship with Colin Gottlieb, now the EMEA chief executive of Omnicom Media Group. The pair say they remain friends and will no doubt keep in touch. However, Manning plans to leave the media agency world and, after 27 years, his talents will be missed.