Neonatal cardiosurgery is nowadays an integral part of treatment of congenital heart disease. At present it is possible to correct completely with a feasible risk heart diseases in the majority of neonates (73%) with a critical congenital disease. Most frequently these disease defects are operated during the first two weeks of life (78% of all operations). In the strategy of surgery optimal timing and selection of the most suitable operation is essential to ensure in time favourable conditions for child growth and development and a long high-quality life. The tactics and therapeutic results in contemporary neonatal cardiosurgery are illustrated by the authors' experience with 174 neonates operated on for congenital critical heart defect in 1991-1993 in the Pediatric Cardiocentre, University Hospital Prague-Motol.