In this article the question of formation and definition of responsibility of participants of construction for untimely performance of work according to the project at a stage of implementation of the investment and construction project is considered. Untimely performance of construction works is a factor which reducesoverall performance of all design and construction conveyor. In operation and estimates of responsibility of their performers are devoted to research of the reasons of inopportuneness of performance of construction works, influence of inopportuneness of performance of separate works on terms of delivery of object many works of domestic and foreign scientists. At the same time some questions of formation of responsibility of participants ofconstruction needfurther studyand justification. In article the question of application of executive schedule diagrams and a method of statistical modeling of PERT for formation and definition of responsibility of participants of construction for untimely performance of work according to the project at astage of implementation of the investment and construction project is considered. The proposedapproach will allow to make reasonably administrative decisions and will reduce time of their acceptance.