The hire of Di Leo was announced by the agency in April last year and she joined in July, but left at the end of the last year.
Di Leo also took on a shareholding in the business, which she has now sold back. She took on a senior role at a key time in its growth - arriving a year after co-founder Katie Perrior left to become Theresa May's comms chief.
Di Leo's LinkedIn profile describes her iNHouse role as working alongside co-founder Jo Tanner to "jointly manage the business to develop it into a high level advisory consultancy".
She has now set up MDL Strategy. She told PRWeek of the new venture: "I'm partnering with senior independent colleagues, bringing together a bespoke mix of skills and experience, combined with the ability to build partnerships that make a difference. We'll remain focused on that model."
Clients of iNHouse have included Diageo, Gatwick, News UK, Starbucks and Microsoft, and it is well known in political circles not just for Perrior's record of working with May and before that Boris Johnson, but also for sponsoring a prominent lounge at party conferences. The agency now has seven staff.