The article discusses the issue of the influence of legal and moral sanctions on the effectiveness of law.First, the author defines the basic terms connected with the relevant problem, such as legal sanctions, moral sanctions, effectiveness of law and their kinds. Next, the discussion mainly focuses on the behavioural effectiveness, which is linked to the issue of observance of law.In reply to the question on what makes people act in accordance with law, particularly when it provides for patterns of behaviour that are burdensome to them, the Author states that legal sanctions are merely one of the factors conditioning the effectiveness of law. This stems, among others, from the fact that self-imposed legal motivation is rather quite a rare ...