The appointment is part of a drive for galvanising communications and event management at Grass Roots.
A focus on driving international development is also part of the strategy for Grass Roots this year.
Litzow will work closely with director of client relationships Simon Maier and operations directors Ainsley Proctor, for event management, and Karen Giles for support services.
Grass Roots global head of events Nick Bender said: "I am really excited about this next phase of our development and will be focusing my time on strategic opportunities, working with the divisional directors at each of our UK locations to help them grow their business collectively. I will also be working with other Grass Roots UK leaders to build out opportunities between our businesses and continue to drive our international development strategy for events."
Litzow has previously worked as vice-president for global events at software company SAP, as well as at Jack Morton Worldwide as a global strategist.
Joining Litzow’s team is Warren Hillier as commercial and measurement director, responsible for pricing and the further development of the Grass Roots’ event measurement tools.
Hillier was formerly finance director for the delegate management services business based in Fleet.
Litzow said she planned to "enhance Grass Roots’ offering with the latest technology and techniques" to provide greater value for clients.