VKalVrt - package for vertex reconstruction in ATLAS.

A universal vertex reconstruction package VKalVrt is presented. It allows using of different constraints, cascade decays reconstruction and has a possibility to use robust versions of fitting functional. Based on Kalman filter approach package is fast enough to deal with hundreds of tracks. Descriptions of basic features, used algorithms , calling sequences are given. Some results obtained with VKalVrt package in primary and secondary vertices reconstruction are presented.