The paper examines the element of joint commission in offences involving negligent concurrent causation of harm. It considers approaches to defining joint commission, its possible external manifestations depending on the type of negligence involved, and its substantive and procedural significance. Analyzing courts' practice and scholarly positions, the author argues that a mere «coincidence of actions» or a «convergence of causal links» does not constitute genuine joint commission. Its defining element is conscious and volitional interaction between the relevant actors. Particular attention is given to the distinctions between joint commission under intentional and negligent forms of fault, including conscious negligence and criminal recklessness. The author observes that a distinctive feature of the joint nature of a negligent offence is that it manifests itself in fact as a pre-offence stage, which is not of criminal-law relevance if the consequences under criminal law do not occur. The paper also addresses the classification of negligent conduct as a jointly committed offence where concurrent contributors do not recognize a socially dangerous nature of their acts or omissions to act. To conclude, the study explains the significance of the joint nature of a negligent offence and its implications for the individualization of punishment for concurrent contributors, the conduct of uniform criminal proceedings in respect of all culpable persons, and the civil law procedure for compensating harm caused by the offence.