Traditional energy and material technologies can have unwanted environmental impacts, so researchers seek greener alternatives in nanotechnology. During the past decades of research, nanomaterials have been explored for applications ranging from solar panels to fertilizers. It has yet to be determined if they are a safer alternative to the energy generation and production methods that are currently in use. Real-world nanotechnology application is limited, but it will increase with time, and it is essential that the field expands in a way that minimizes damage to living organisms. To assess the consequences of nanomaterials on human health and the environment, researchers must look at their production, service life, disposal, toxicity, and persistence. It is challenging to assess even the most common nanomaterials, such as graphene, titanium dioxide, and zinc oxide, because of the interdisciplinary work required. Sciences from chemistry to physics, biology, and ecology are needed to extrapolate from the interactions of particles and cells to the organism-scale consequences of exposure, and from there to an ecosystem scale. Researchers have employed laboratory experiments, mathematical modeling, and the practical examples that are available to outline the possible consequences of nanotechnology. This chapter provides a glimpse of this ongoing research and some future directions.