For rescission of a default judgment to be granted under Order 9 Rule 63 of the High Court Rules, 1971, an applicant must demonstrate 'good and sufficient cause' by establishing: (1) a reasonable explanation for the default; (2) that the application is brought bona fide; and (3) a bona fide defence on the merits with prospects of success. Wilful default occurs only when a party, with full knowledge of service or set down and the risks of default, freely decides to refrain from appearing. Where a party has actively participated in proceedings by entering appearance, filing requests for particulars, and submitting pleadings, such conduct is inconsistent with wilful default and supports rescission where triable issues exist.