In 1984 Greenstein established her own firm, engaging in several projects of public space in Haifa and in the north of Israel.
The office is located on Mount Carmel, Haifa, and engages in a wide range of projects, mainly for the public sector, on a national, regional and local level.
The firm participated in invited and open competitions in Israel and abroad and was awarded several first prizes and citations.
Alongside her professional work, Greenstein dedicated substantial time to academic teaching of landscape architecture, as an adjunct professor at the University of Oregon in 2000, and as a senior lecturer, from 1985 till today at the Technion Department of Landscape Architecture in Haifa.
In 2013 she served as the chairperson of the steering committee for the Annual Conference of the Israeli Landscape Architects Association, which took place in Haifa, with over 500 participants.