This treatise is on the collaboration for ecosystem between Helen Mayer Harrison and Newton Harrison, pioneers of ecological and environmental art. The Harrisons have become world-renowned for using art to tackle environmental problems on a global scale. They maintained separate careers until the end of the 1960s. Newton as an artist, and Helen as a sociologist as well as an educator. In 1970, they decided to put the two careers together and to do no work that did not include the environment. It was a lifetime artistic decision. Then Helen and Newton began their artistic collaboration that would last for the next half-century. The Harrisons are famous, but surprisingly little-known artists. This study comes from the basic question, “Who are the Harrisons?” This involves the following three questions: What kind of career have Helen and Newton each made? How did the two develop their collaboration? Why did they choose art for the ecosystem? Following the chronology, this essay examines the development process of their artistic collaboration and explores their motives for collaboration for the ecosystem. This will clearly reveal the Harrisons, who have made the collaboration itself a successful work of art on an existential level.