1. In a network environment that includes a source client and a plurality of destination clients, the source client being capable of sending electronic messages to the plurality of destination clients, the network environment including one or more certificate servers that are capable of validating and providing certificates for at least some of the one or more destination clients to the source client, each certificate including encryption information needed to encrypt to the corresponding destination client, and including self-verification information to allow for a determination that the certificate does indeed correspond to the corresponding destination client and has not been revoked, a method for the source client encrypting a message to be sent to at least one of the destination clients, the method comprising the following: an act of the source client accessing an electronic message to be transmitted to a destination client of the plurality of destination clients; an act of determining that the electronic message is to be encrypted before transmission to the destination client; an act of generating a request to access only a portion of a certificate corresponding to the destination client, the portion including encryption information needed to encrypt the electronic message so as to be decryptable by the destination client; an act of transmitting the request to the certificate server; an act of receiving only the requested portion of the certificate from the certificate server; and an act of using the encryption information to encrypt the electronic message.