Advanced training in cardiothoracic surgery has become more prevalent in the setting of increased complexity of interventions. Minimally invasive techniques, transcatheter and endovascular interventions, and rapid growth in mechanical circulatory support and transplant have led approximately 40% of trainees to pursue additional training. Available data suggest trainees seek additional training for 3 main reasons: gain an additional skillset, improve candidacy for a job, and/or increase proficiency in basic areas. This review provides an analysis of existing literature, categorized by specialty (cardiac, thoracic, and congenital) to determine areas where additional training is of benefit.