On a spiritual level, there really is no such thing as confidentiality. That said, it is important that people are treated with respect, and that includes allowing everyone to determine what they do and do not want to share with others. At any point feel free to let us know about any concerns you have for confidentiality. For privacy purposes we keep our membership information on a standalone computer that is not connected to the internet.
And speaking of respect, if you are unknown to us and wish join the Church, we will expect assurance that you are who you say you are, and that you live where you say you live. In other words, be prepared to provide some kind of valid identification and physical address verification with your application for membership. It is an unfortunate truth these days that there are individuals who seek company with internet-based organizations for less than honorable intentions.