Fitzpatrick, who is a barrister and will also be a partner in the Norton Rose Fulbright real estate team, joins the firm from law firm Bryan Cave Leighton Paisner (BCLP).
Fitzpatrick, a member of the Compulsory Purchase Association, was also a partner at BCLP and worked at the company for 18 years.
According to a statement from Norton Rose Fulbright, Fitzpatrick handles all aspects of planning law and practice. She has "significant experience in London regeneration and redevelopment, compulsory purchase, high rise development, infrastructure, energy infrastructure, road and rail, and large scale multi-use schemes", it added.
Fitzpatrick said: "The UK real estate market is highly dynamic with a diverse range of participants and investors who require comprehensive legal advice, including in relation to planning. I look forward to growing the team."
Wasim Khan, partner and head of the London real estate practice, said: "Clients require teams that can offer strategic advice across the board and have in-depth knowledge of major infrastructure, transport and regeneration projects.
"Sarah will be a great asset to our UK real estate team and will extend the breadth of our offering to clients."
A previous head of planning at Norton Rose Fulbright, Duncan Field, joined specialist planning law firm Town Legal at a partner in February last year.