The early works were influenced by American land art and Japanese gardens, reconciling two approaches to the art and nature, art in nature dialectic. Expanding her repertoire of materials, Lay began to use welded steel in the 1980s as a way to incorporate drawing into her projects, adding a linear element as well as an expressive one, a further adumbration of the emotive/rational dichotomy intrinsic to her work, an opposition that gives it tension. By the 1990s, Lay became more focused on the psychological and spiritual aspects of abstraction, on its subliminal content and the universality of its language. She also began to create installations that interacted closely with the architecture of the space, her forms—while abstract signs and symbol from the biomorphic to the geometric and linguistic—a compelling combination of the personal and the more objective. Process and the hand-made have always been important to her, inspired by feminist art and the imagery and techniques of the indigenous cultures of the Americas, Africa and the Pacific Islands. In her search for existential meaning, Lay merges a version of the collective unconscious with structuralist and post-structuralist theories, Dadaism and Surrealism, postmodernism and contemporary strategies. Toward the end of the decade, Lay began to create mixed-media constructions that were often a cross between reliefs and paintings in the form of mandalas.