What are the requirements for a judge to vary or cancel a child support order?

A material change of circumstances must be one that affects the child (Gordon v. Goertz, 1996 CanLII 191 (SCC), [1996] 2 S.C.R. 27 at para. 49). I must assume the correctness of the original decision and only consider changes in circumstances that have come about since the making of the present order (para. 11). The particular change "must have altered the child's needs or the ability of the parents to meet those needs in a fundamental way" and should represent a "distinct departure from what the court could reasonably have anticipated in making the previous order" (para. 12). These requirements are summarized at para. 13, as follows: It follows that before entering on the merits of an application to vary a custody order the judge must be satisfied of: (1) a change in the condition, means, needs or circumstances of the child and/or the ability of the parents to meet the needs of the child; (2) which materially affects the child; and (3) which was either not foreseen or could not have been reasonably contemplated by the judge who made the initial order. Variation or Cancellation of Child Support