Competition authorities are known for imposing enormous fines on companies that have infringed the law. However, most authorities are equally active in educating, deliberating, influencing, or preventing, to which end they have different enforcement instruments at their disposal. Imposing a fine (or issuing an order, or imposing a periodic penalty payment) through a fully adversarial procedure can be characterized as formal, based on a vertical relationship between companies and competition authorities, deterrence-based, punitive, reactive and case-specific. By contrast, alternative enforcement entails a deviation from command-and-control style enforcement by using enforcement instruments. It can be characterized as informal, horizontal, compliance-based, restorative, preventative or efficient, or a combination of one or more of the above. This research analyzes and compares the use of certain alternative enforcement instruments (negotiated procedures, markets work, individual guidance, and compliance programs) by the Dutch Autoriteit Consument en Markt, the UK Competition and Markets Authority, and the French Autorite de la Concurrence. It is an interesting work for both academics and practitioners in the field of competition law and enforcement. Dissertation [Subject: Commercial Law, Comparative Law]