At
Harvard University, Walker had been deeply influenced by his professor,
Hideo Sasaki. After graduating, he worked for Sasaki. Shortly thereafter, they both went into partnership to form Sasaki Walker Associates in 1957. Walker and Sasaki went their separate ways in 1983, and Walker entered a partnership with landscape architect
Martha Schwartz.[7]
In the early 1990s, Walker formed Peter Walker and Partners.[7] In a 1993 review, Walker was one of four landscape architects named as representative of the new generation.[8] The company developed into an interdisciplinary firm that employs around thirty to forty landscape architects. The company has received many awards[9] and co-designed the
World Trade Center Memorial in New York with architect
Michael Arad.[10]
Walker designed the garden for the
Nasher Sculpture Center. In 2013 he was involved in a public argument with the architect of a neighboring building,
Museum Tower, because the glare from the glass was damaging the vegetation. Walker described it as "public desecration".[11]
Peter Walker is also a co-author of Invisible Gardens, which touches on the modernist movement in the United States and the comparison of other landscapes to those in Europe.[citation needed] The book discusses influential landscape architects, including Sasaki.
Walker, Peter, and Leah Levy. Peter Walker: Minimalist Gardens. Washington, DC: Spacemaker, 1997. Print.[26]
Invisible Gardens: The Search for Modernism in the American Landscape. Walker, Peter, and Melanie Simo. Cambridge, Massachusetts: MIT-Press, 1998. Print.Cambridge, Massachusetts: MIT-Press, 1998.[27]
Peter Walker and Partners: Defining the Craft. Walker, Peter. San Rafael, CA: ORO Editions, 2005. Print.[28]