Chest tube thoracostomy is a common procedure performed for drainage of unwanted air or fluid from the thoracic cavity. The most common indications for chest tube thoracostomy include pleural infection, malignant pleural effusion, pneumothorax, and hemothorax. Evidence supports the use of small-bore chest tubes (SBCT) for the majority of indications with few exceptions. SBCTs are primarily inserted using ultrasound guidance by Seldinger technique. The indications, insertion techniques, and complications associated with SBCTs will be reviewed in this chapter.