|This article does not cite any references or sources. (March 2011)|
Ocean colonization is the theory and practice of permanent human settlement of oceans. Such settlements may be seasteads floating on the surface of the water, or exist as underwater habitats secured to the ocean floor, or in an intermediate position.
One primary purpose of ocean colonization is the expansion of livable area. Other possible benefits include expanded access to undersea resources, novel forms of governance (for instance micronations), and new recreational activities.
Lessons learned from ocean colonization may prove applicable to space colonization. The ocean may prove simpler to colonize than space and thus occur first, providing a proving ground for the latter. In particular, the issue of sovereignty may bear many similarities between ocean and space colonization; adjustments to social life under harsher circumstances would apply similarly to the ocean and to space; and many technologies may have uses in both environments.
See also 
- Principality of Sealand
- Atmosphere colonization
- Artificial island
- Freedom Ship
- Underwater habitat