A method for monitoring Session Initiation Protocol presence information and transmitting SIP presence notifications based on a detected sequence of events over a time period, the method comprising: receiving, at a presence server processing device from a client entity, a SIP subscribe message to a presentity that includes a sequence of events which define a trigger that controls when the presence server sends a SIP notify message to the client entity, wherein the SIP subscribe message further indicates a time period parameter defining a time limit for the occurrence of at least one of the events in the sequence of events, wherein the sequence of events comprises a plurality of events of different types, wherein at least two events in the sequence of events occur at different times over a time period associated with the time period parameter, and wherein an event comprises a state transition from one value to a different value for one or more SIP presence information elements stored in a memory at the presence server; receiving, at the presence server, presence information in one or more SIP publish messages containing a value for one or more of the SIP presence information elements stored in the memory at the presence server and monitoring, by the presence server, the presence information based on the indicated time period parameter to detect an occurrence of the sequence of events set forth in the SIP subscribe message; and sending, by the presence server, the SIP notify message to the client entity when the monitored presence information satisfies the trigger, wherein the monitored presence information satisfies the trigger defined as one of the following: upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred, but with an occurrence of at least one intervening event; or upon the presence server detecting that at least one of the events in the sequence of events set forth in the SIP subscribe message failed to occur; or upon the presence server detecting occurrence of an additional event that is not included in the sequence of events set forth in the SIP subscribe message; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred but failed to meet the time period parameter. receiving, at a presence server processing device from a client entity, a SIP subscribe message to a presentity that includes a sequence of events which define a trigger that controls when the presence server sends a SIP notify message to the client entity, wherein the SIP subscribe message further indicates a time period parameter defining a time limit for the occurrence of at least one of the events in the sequence of events, wherein the sequence of events comprises a plurality of events of different types, wherein at least two events in the sequence of events occur at different times over a time period associated with the time period parameter, and wherein an event comprises a state transition from one value to a different value for one or more SIP presence information elements stored in a memory at the presence server; receiving, at the presence server, presence information in one or more SIP publish messages containing a value for one or more of the SIP presence information elements stored in the memory at the presence server and monitoring, by the presence server, the presence information based on the indicated time period parameter to detect an occurrence of the sequence of events set forth in the SIP subscribe message; and sending, by the presence server, the SIP notify message to the client entity when the monitored presence information satisfies the trigger, wherein the monitored presence information satisfies the trigger defined as one of the following: upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred, but with an occurrence of at least one intervening event; or upon the presence server detecting that at least one of the events in the sequence of events set forth in the SIP subscribe message failed to occur; or upon the presence server detecting occurrence of an additional event that is not included in the sequence of events set forth in the SIP subscribe message; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred but failed to meet the time period parameter. upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred, but with an occurrence of at least one intervening event; or upon the presence server detecting that at least one of the events in the sequence of events set forth in the SIP subscribe message failed to occur; or upon the presence server detecting occurrence of an additional event that is not included in the sequence of events set forth in the SIP subscribe message; or upon the presence server detecting that all of the events in the sequence of events set forth in the SIP subscribe message occurred but failed to meet the time period parameter.