Howe's responsibilities will cover WH Smith and a range of other retail assignments that have yet to be disclosed. She joins the agency after Easter.
Howe, 35, left Leo Burnett in January this year following the company's merger with D'Arcy. At the time, her intention was to embark on an MBA course.
Howe joined Leo Burnett from DMB&B in 1997 as an account handler on the Kellogg, Heinz Seafood and McDonald's accounts.
She was promoted to head of account management in 1999 and became the deputy managing director a year later. In this role, Howe took responsibility for much of the agency's marketing function following the departure of its marketing director, Claire Durwood.
In January last year, Howe was promoted to managing director, a position that had remained vacant since the previous spring when Stephen Whyte was made chief executive.
Howe said: "AMV is a great agency brand. People know exactly what they are doing: the focus is on clients and creative work. For me it is a very established and stable environment; this contrasts with Burnett, where there were a lot of management changes over the years."
AMV's chief executive, Cilla Snowball, added: "Kate has a good combination of relevant skills that we need at the moment. She has an impressive retail track record and good leadership skills."