Ordered that the order dated May 15, 2009, is affirmed, with costs to the respondents.
To vacate their default in opposing the defendants' motion for summary judgment, the plaintiffs were required to demonstrate both a reasonable excuse for their default and a potentially meritorious claim ( see Donovan v Chiapetta, 72 AD3d 635; Aurora Loan Servs. v Grant, 70 AD3d 986). The determination of what constitutes a reasonable excuse lies within the trial court's discretion ( see Zarzuela v Castanos, 71 AD3d 880; Santiago v New York City Health Hosps. Corp., 10 AD3d 393, 394). Under the circumstances of this case, the plaintiffs' claim of law office failure was insufficient to excuse their failure to oppose the defendants' motion for summary judgment.