Yes, very much so. Domino's founders all came from the financial services industry, and many of Domino's clients work with highly sensitive data — we take security very seriously.
Domino encrypts your data when it's at rest, and when it's in transit, everywhere in the system. We follow modern best practices for securing the platform. Our Cloud offering uses AWS physical infrastructure, which is accredited under a number of advanced security specifications. (Our Enterprise offering installs entirely behind your firewall, on your own hardware, so your data never leaves your network.)