An apparatus for assisting a selection of motion management technique for use with a treatment machine having an energy source, the apparatus comprising: one or more input for obtaining a motion trace of a target in a patient to be treated, and/or for obtaining motion data of a fiducial; and a motion management processor configured to determine motion management data based at least in part on at least a portion of the motion trace of the target and/or at least a portion of the motion data of the fiducial, wherein the motion management data indicates desirability and/or undesirability of one or more motion management option(s); wherein the fiducial comprises one or more of (i) a surrogate inside the patient or (ii) a marker coupled to the patient; and wherein the motion management processor is also configured to output the motion management data for assisting the selection of the motion management technique for use with the treatment machine; characterized in that : the apparatus comprises a synchronous motion detector , wherein the apparatus implements one or more algorithms for determining the desirability and/or undesirability of the one or more motion management options; wherein the synchronous motion detector is configured to determine whether the surrogate or marker moves synchronously with the target; and wherein the motion management processor is further configured to output motion management data indicating that motion management based on the surrogate or marker is undesirable if the surrogate or marker does not move synchronously with the target. one or more input for obtaining a motion trace of a target in a patient to be treated, and/or for obtaining motion data of a fiducial; and a motion management processor configured to determine motion management data based at least in part on at least a portion of the motion trace of the target and/or at least a portion of the motion data of the fiducial, wherein the motion management data indicates desirability and/or undesirability of one or more motion management option(s); wherein the fiducial comprises one or more of (i) a surrogate inside the patient or (ii) a marker coupled to the patient; and wherein the motion management processor is also configured to output the motion management data for assisting the selection of the motion management technique for use with the treatment machine; characterized in that : the apparatus comprises a synchronous motion detector , wherein the apparatus implements one or more algorithms for determining the desirability and/or undesirability of the one or more motion management options; wherein the synchronous motion detector is configured to determine whether the surrogate or marker moves synchronously with the target; and wherein the motion management processor is further configured to output motion management data indicating that motion management based on the surrogate or marker is undesirable if the surrogate or marker does not move synchronously with the target. the apparatus comprises a synchronous motion detector , wherein the apparatus implements one or more algorithms for determining the desirability and/or undesirability of the one or more motion management options; wherein the synchronous motion detector is configured to determine whether the surrogate or marker moves synchronously with the target; and wherein the motion management processor is further configured to output motion management data indicating that motion management based on the surrogate or marker is undesirable if the surrogate or marker does not move synchronously with the target. <EOS>