The conceptual provisions and strategical aspects of the monitoring of the chemical composition of the atmosphere at manned spacecrafts and space stations which can be used in the execution of long-term and interplanetary space flights are proposed and substantiated. The major risk factors of the change in the composition of the atmosphere in the case of interplanetary space flights are formulated. Current advances in the field of monitoring are critically evaluated, which allows the choice of directions for new domestic designs to be substantiated. A promising version of an analytical complex for the operational control of the quality of the air in manned spacecrafts and space stations is described that takes into account the major risk factors. To provide the partial overlapping of the nomenclature of the detectable substances in terms of the most important (critical) compounds, it is proposed to simultaneously use several methods of gas analysis based on different physical principles. It is concluded that the implementation of such a monitoring system will make it possible to analyze a wide range of substances on a full scale and will provide an operational analysis of the quality of the air in manned spacecrafts and space stations, not only in usual operations but also in contingency (emergency) events.