Since the 19th and early-20th century, plastics have become ubiquitous in the world. Plastics have outgrown most man-made materials: their global volume production has surpassed that of steel production in the late 1980s (Fernandez et al., 2018). Plastic production continues to increase and undesirable impacts from plastic pollution have proliferated throughout the world, in our lands, rivers and oceans, as well as in animals and human foods. It is time for the world to solve this problem. Banning plastics is not sufficient nor immediately practical. Just as for CFCs, we need to engineer alternatives, but in the plastic case, we also need to clean the environment due to the long plastic lifetimes. Some of the needs include: design and manufacture plastic alternatives for varied applications, from packaging to automotive and fishing; understand, model, and forecast plastic transports and dispersion in our estuaries and oceans, combining fundamental dynamics with uncertainty quantification, data assimilation, and machine learning; develop and build intelligent autonomous robots for optimized plastic sensing and cleaning, on land and at sea; harvest energy or other useful by-products from plastic waste without new pollution; integrate all of these systems into practical world and regional solutions. The MIT Environmental Solutions Initiative (MIT-ESI) aims to tackle this challenge through the expertise of our interdisciplinary faculty, ranging from materials, to manufacturing and design, to smart sensing and advanced computational modeling and data-driven learning. Through our approaches and collaborations, our long-term goal is to develop a plastic free environment that will ensure the health of our planet.