The ocean’s surface is becoming an increasingly crucial resource to support the expanding human population by providing both food and living space. Additionally, there is a need to establish designated compensation areas for regions affected by rising sea levels. Currently, the use of aquatic structures is mostly confined to buildings on floating pontoons. This limitation may be also due to the absence of a well- established design typology for floating structures. In this chapter, we aim to create a typology that employs design principles to enable aquatic structures to float. We propose three distinct types based on various buoyancy properties as a foundation for discussion, and we illustrate them with examples. The example of the SeaManta incorporates air chambers within its artificial floating reef design. In contrast, the SeaOases uses air-filled membranes to create its overall shape. The third type exemplified by the SeaSurveyor utilizes external buoyancy bodies as flotation aids. Using the typology together with drivers of design such as the natural environment, this study demonstrates how aquatic structures can help protect and revitalize marine ecosystems and ensure sustainable global food security. Further investigations will show which aquatic structures can be developed to design additional marine futures like for the expansion of humankind onto sea.