As the Cayman Islands is an internally self-governing British Overseas Territory (BOT), there is no distinct Cayman Islands citizenship but rather a form of citizenship common to all BOTs, formally known as British Overseas Territories Citizenship (BOTC). BOTC law in many cases mirrors that which governs British Nationality. It is based on a mixture of restricted ius soli and ius sanguinis. Presently, one may acquire BOTC at birth, if born in the BOTC to at least one parent who is a BOT citizen or settled in a BOTC. One may also acquire BOTC by means of descent if born outside of the British Overseas Territory to a BOT citizen who holds BOTC by means other than by descent.
In terms of acquiring BOT Citizenship after birth, this is possible (for adults) through naturalisation. Where an applicant is married to a BOT citizen the acquisition of citizenship by naturalisation is easier, for instance, the residency period in this case is reduced from five, to three years. Children may also become BOT citizens through a process known as Registration.
Any person who is a BOT citizen by virtue of a connection with the Cayman Islands is entitled to hold a BOT Passport. Being Caymanian (effectively being a national of the Cayman Islands) is a status that is distinct and apart from being a BOT citizen. It is possible to be a BOT citizen and hold a BOT Passport without being Caymanian, and vice-versa.
With respect to dual citizenship, this is allowed in the Cayman Islands. Any BOT citizen acquiring second citizenship will not lose their BOTC. Foreign nationals who acquire BOT Citizenship are not required by Cayman Islands (or British) law to renounce their original nationality. Furthermore, any person who is a BOT citizen is eligible to apply for registration as a full British citizen and thereupon hold a full British passport in addition to a BOT Passport.