Presence and availability information is disseminated through a computer system architecture having four interactive elements. A schedule publication element acquires information about user schedules. A schedule management element communicates with the publication element to acquire schedule information and to store integrated schedule information in a storage system. A schedule distribution element acquires schedule information from the schedule management element and selectively disseminates the information to subscribers who have interacted with a schedule subscribing element. Both current and future presence and availability information is thus collected and disseminated in an orderly manner.