In a negligence action to recover damages for personal injury, loss of services, etc., the defendant appeals from an order of the Supreme Court, Westchester County, dated October 29, 1963, which denied its motion to dismiss the complaint for lack of prosecution (CPLR 3216). Order reversed, without costs; motion granted and complaint dismissed. Issue was joined October 4, 1961, at which time a demand was made for a bill of particulars. The plaintiffs did not serve a bill of particulars, and nothing was done to place the action on the Trial Calendar until the motion to dismiss for lack of prosecution was made 23 months later (on Sept. 4, 1963). The explanation of plaintiffs’ counsel for the delay was that the papers were misfiled through inadvertence. In our opinion, such explanation is insufficient to excuse the unreasonable delay in prosecuting the action; hence, it was an improvident exercise of discretion to deny the motion to dismiss the complaint (Keating v. Smith, 20 A D 2d 141; Gallagher v. City of New York, 19 A D 2d 623). Beldock, P. J., Kleinfeld, Christ, Brennan and Hopkins, JJ., concur.