Most countries throughout the world directly border on seas and oceans, which implicitly imposes on their new responsibilities and specific tasks. In this respect, among internationally accepted solutions that have put views and ideas into practice stands the United Nations Convention on the Law of the Sea (UNCLOS). In our case, we compare policies on the marine/maritime cadastre (marine information system) among Latvia, Lithuania, and Egypt through the lenses of global ocean governance and the internationally recognized perspective of the European Union Integrated Maritime Policy. This policy is based on cross-cutting aspects such as Blue Growth and maritime spatial planning, which have a sound regulation framework at both the regional level and the sea basin level. However, at the same time, much is determined by each country’s geographical location, their neighboring countries, and their possibilities and ability to cooperate. The maritime cadastre is also nothing more than the realization of good practice in accordance with accepted standards and international guidelines. Each region has its own leaders in the field, where cooperation is developed and enshrined in law. Other factors include successful interaction between different institutions and the level of support from both professionals and the wider public. In this case, our focus is on ecological, green development, and further development plans at sea. Items under the microscope include development of wind farms, other environmentally friendly energy, protected areas, traditional coastal fishing, fish resources, tourism, and the natural landscape, along with many other issues. We look at existing developments in each of the three countries covered, solutions with technically fixed parameters, as well as plans and further development for growth of the maritime cadastre in our shared digital world with its geographic information systems (GIS), augmented reality, and innovations. We also embrace planning and growth in terms of the Marine Spatial Data Infrastructure (MSDI), which includes high-precision measurements at sea and from space.