The number of incidents where police officers are first responders in critical situations with severe threat circumstances has drastically increased. A major challenge for these first responding officers is to properly evaluate the situation and decide how to further proceed and to assess and choose the most appropriate strategy. The appropriateness of this decision is highly critical as it has a strong impact on the potential success of the operation as well as on the potential impacts, scene environment (e.g. witnesses, involved civilians, etc.) and consequences. So the SHOTPROS project aims to investigate the influence of psychological and contextual human factors (HFs) on the behaviour of decision-making and acting (DMA) of police officers under stress and in high-risk operational situations in order to design better training for police officers to improve DMA Performance. SHOTPROS will develop a Virtual Reality (VR) solution to experimentally assess the degree to which these factors influence DMA behaviour. Subsequently the project will develop a HF-rooted training curriculum and a corresponding VR training solution to provide a comprehensive framework for practical training for decision-making and acting under stress and in high-risk (DMA-SR) situations in order to improve performance.The training will increase DMA-SR performance which will lead to better and more correct decisions (from several perspectives, e.g. law, ethic, etc.), to keep the guidance in threatened situations, to minimise use of force occurrences, and accordingly, to maximise the avoidance of casualties and collateral damage, such as panic and cascading or escalating effects. SHOTPROS involves 6 law enforcement agencies (LEA) as it sees the capabilities of effective, efficient and “correct” DMA-SR of police forces as an utmost important part of a European Security Model and a high need for the daily combat against crime, terrorism, CBRNe threats and radicalisms.