In line with reducing the invasiveness of interventions in permanent teeth and changes towards more biological approaches, there have also been moves away from traditional restorative approaches to managing primary teeth where carious dentine/lesions were completely excised and a restoration placed. The Hall Technique is a method for managing carious primary molar teeth where a preformed stainless-steel crown, also known as a preformed metal crown, is seated over a tooth, sealing in, and not removing carious tissue. This chapter discusses the rationale behind the Hall Technique, an outline of the clinical procedure to carry it out, its indications and contraindications, together with the evidence supporting its use. The Hall Technique has been found to be acceptable to children and preferred to more invasive treatment options. Like all dental treatment options, it requires careful case selection, precise carious lesion and pulpal status diagnosis (clinically and radiographically), good patient management, and excellent parental cooperation. The Hall Technique has been shown to be a durable (being likely to last the lifespan of the primary molar) and economical management option for primary molars with carious lesions, which in addition offers the benefit of full coronal coverage, reducing the risk of future carious lesion development. As part of our everyday armamentarium in paediatric dentistry, the Hall Technique is an effective management option for controlling carious lesions in primary molars.