A system and method for determining a security encoding to be applied to a message being sent by a user of a computing device. In one broad aspect, the device comprises a processor configured to: determine whether a general message encoding configuration setting indicates that when a security encoding is to be applied to a message then the security encoding is to be established by a policy engine; if the general message encoding configuration setting so indicates, query the policy engine for the security encoding to be applied to the message; otherwise, determine the security encoding to be applied to the message in accordance with a user-selected security encoding; and apply the determined security encoding to the message prior to transmission of the message to at least one recipient.