Dr Nikki Mills is a New Zealand based pediatric ENT surgeon, who has a special clinical and research interest in breastfeeding and is also an International Board Certified Lactation Consultant. Nikki worked for many years at the Starship Children’s Hospital in Auckland, moving in 2020 to Nelson Hospital in Nelson, New Zealand. In this first episode of an in-depth 3-part conversation, Pam and Nikki take a deep dive into Nikki’s groundbreaking anatomical dissection studies of the floor of mouth fascia, which reveal the true nature of the infant lingual frenulum. They discuss the implications of her studies for the biomechanical model of infant suck during breastfeeding, the diagnosis of ‘posterior tongue-tie’, the decision whether or not to proceed with frenotomy, and the risks associated with frenotomy. Dr Pamela Douglas is a GP who works in breastfeeding medicine at the Possums Clinic Brisbane, with special clinical and research interest in breastfeeding, having first qualified as an International Board Certified Lactation Consultant in 1994. Pam is a GP-researcher and founder of the evidence-based Neuroprotective Developmental Care (or 'Possums') programs www.possumsonline.com. Pam is also author of The discontented little baby book: all you need to know about feeds, sleep, and crying.