An organizer may send information relating to an event to participants via text messaging without having participants' texting numbers. Particularly, organizer may be associated with a texting number. Organizer sets event's start/end times, and provides email addresses for event invitees. Email requests invitees' texting numbers to participate in event. Texting numbers are stored, and encrypted respectively as identifiers. Organizer's message for participants is sent as text message to participants' texting numbers between event's start/end, and may be sent as if the message originated from organizer's texting number. When event ends, participants' texting numbers are deleted unless a participant participates in organizer's later ending event. In response to invitation to organizer's later event, a received participant's texting number may be encrypted as later identifier, and compared with identifier from earlier event. If a match, organizer's text message sent to participant during prior event is included in organizer's or participant's conversational history.