The most important issues of strategies and tactics for providing multidisciplinary care to victims with polytrauma are the timing and methods of surgical stabilization of long bone fractures, referred to as the objective choice of optimal surgical tactics. In 4 articles, the methodology of informed choice and the content of surgical tactics for stabilizing long bone fractures in the acute period of polytrauma are presented. Objective - development and testing of the methodology for the informed choice of surgical tactics for stabilizing long bone fractures in the acute period of polytrauma. Materials and methods. The cross-sectional design of the study is based on the formation by a selective method of a data array of the required number of clinical observations in order to represent the general set of characteristics of a “typical” polytrauma. For this purpose, two arrays of clinical cases of polytrauma were formed from victims who were treated in level III trauma centers in St. Petersburg from 2004 to 2017: research array No. 1 of “typical” polytrauma (n = 353) and control array No. 2 (n = 165). On the first array, the methodology for the objective choice of rational surgical tactics was created, and the control one was used to test and objectively evaluate the effectiveness of the developed prognostic model. When solving statistical problems, program modules of the STATISTICA 10.0 for Windows system were used. The effectiveness of methods for assessing the severity of polytrauma and the developed prognostic model was compared according to their calibration (Hosmer-Lemeshow criterion) and discriminatory ability using ROC analysis. Results. The methodology for a reasonable choice of surgical tactics for stabilizing long bone fractures in the acute period of polytrauma includes five elements. The first is the working array of “typical” polytrauma, representing the typical structure of the incoming flow of victims of level III trauma centers in terms of severity, location and structure of injuries. The second is the working prognostic model created on the basis of an objective classification of polytrauma cases according to specified mortality parameters. The third is objective methods for determining the severity of polytrauma (NISS) and severity of condition (Military Field Surgery-State upon Admission scale). The fourth is a well-founded method for choosing the optimal surgical tactics. The fifth is an expert prognostic model for the informed choice of optimal surgical tactics for the acute period of polytrauma. Conclusion. The most effective methods for objectively determining the severity of polytrauma are NISS index (AUROC = 0.911 ± 0.21) and Military Field Surgery-State upon Admission scale (AUROC = 0.928 ± 0.19). The prognostic model of three groups, created on the basis of an objective classification of polytrauma according to specified mortality parameters, based on calculations of the NISS index and Military Field Surgery-State upon Admission scale, is a reasonable way to select the optimal tactics for surgical stabilization of long bone fractures in the acute period of polytrauma. The effectiveness of the expert predictive model for the informed choice of tactics for surgical stabilization of long bone fractures in the acute period of polytrauma is assessed as high: area under ROC = 0.901 ± 0.25, sensitivity = 83 %, specificity = 74 %.