An elevator system comprising: a first elevator group controller (GC-1) configured to control a first elevator car of a first elevator group; a second elevator group controller (GC-2) configured to control a second elevator car of a second elevator group, the second elevator group controller (GC-2) in bi-directional communication with the first elevator group controller (GC-1); a destination entry device configured to receive a destination call from a passenger, the destination call identifying a source floor and a destination floor; at least one of the first elevator group controller (GC-1) and the second elevator group controller (GC-2) determining that a journey from the source floor to the destination floor requires a first phase utilizing the first elevator group and a second phase utilizing the second elevator group; at least one of the first elevator group controller and the second elevator group controller allocating the first elevator car for the first phase and allocating the second elevator car for the second phase; characterised in that: allocating the first elevator car for the first phase comprises generating a first destination call; and detecting a load of the first elevator car and terminating the first destination call if the first elevator car load is zero; if the load in the first elevator car is not zero, one or more of the elevator group controllers (GC-1, GC-2) determines if the next stop of the first elevator car is the end of the first phase of the journey; if the next stop is the end of the first phase, one or more of the elevator group controllers (GC-1, GC-2): determines the time the passenger will arrive at a landing to commence the second phase of the journey; and registers a second destination call corresponding to the second phase of the journey; and in that allocating the second elevator car for the second phase comprises: generating a second destination call; and detecting a load of the second elevator car and terminating the second destination call when the second elevator car load is zero. a first elevator group controller (GC-1) configured to control a first elevator car of a first elevator group; a second elevator group controller (GC-2) configured to control a second elevator car of a second elevator group, the second elevator group controller (GC-2) in bi-directional communication with the first elevator group controller (GC-1); a destination entry device configured to receive a destination call from a passenger, the destination call identifying a source floor and a destination floor; at least one of the first elevator group controller (GC-1) and the second elevator group controller (GC-2) determining that a journey from the source floor to the destination floor requires a first phase utilizing the first elevator group and a second phase utilizing the second elevator group; at least one of the first elevator group controller and the second elevator group controller allocating the first elevator car for the first phase and allocating the second elevator car for the second phase; characterised in that: allocating the first elevator car for the first phase comprises generating a first destination call; and detecting a load of the first elevator car and terminating the first destination call if the first elevator car load is zero; if the load in the first elevator car is not zero, one or more of the elevator group controllers (GC-1, GC-2) determines if the next stop of the first elevator car is the end of the first phase of the journey; if the next stop is the end of the first phase, one or more of the elevator group controllers (GC-1, GC-2): determines the time the passenger will arrive at a landing to commence the second phase of the journey; and registers a second destination call corresponding to the second phase of the journey; and in that allocating the second elevator car for the second phase comprises: generating a second destination call; and detecting a load of the second elevator car and terminating the second destination call when the second elevator car load is zero. allocating the first elevator car for the first phase comprises generating a first destination call; and detecting a load of the first elevator car and terminating the first destination call if the first elevator car load is zero; if the load in the first elevator car is not zero, one or more of the elevator group controllers (GC-1, GC-2) determines if the next stop of the first elevator car is the end of the first phase of the journey; if the next stop is the end of the first phase, one or more of the elevator group controllers (GC-1, GC-2): determines the time the passenger will arrive at a landing to commence the second phase of the journey; and registers a second destination call corresponding to the second phase of the journey; and in that allocating the second elevator car for the second phase comprises: generating a second destination call; and detecting a load of the second elevator car and terminating the second destination call when the second elevator car load is zero. generating a second destination call; and detecting a load of the second elevator car and terminating the second destination call when the second elevator car load is zero.