This week we review a recent report from the Boston fetal intervention group about fetal aortic valvuloplasty. What fetal/maternal factors are associated with improved outcomes or technical success of this procedure? What factors are associated with serious adverse events? Who is the 'optimal' candidate for this type of intervention? Why is larger LV size associated with improved technical success? What other types of fetal interventions are being attempted by the Boston team? Drs. Ryan Callahan and Wayne Tworetzky of The Children's Hospital of Philadelphia and Boston Children's Hospital, respectively, share their deep knowledge of fetal intervention this week. https://doi.org/10.1016/j.jacadv.2024.100835