1 The development of a novel supplemental coding system for investigating the practice elements of attachment-based interventions Ahmed Riaz Mohamed 1,2,4 , Paula Sterkenburg 1,3 , Esmé van Rensburg 2 & Carlo Schuengel 1 1 Department of Clinical Child and Family Studies and Amsterdam Public Health Research Institute, Vrije Universiteit, Amsterdam, Netherlands, 2 Department of Psychology, North- West University, Potchefstroom, South Africa, 3 Department of Psychotherapy, Bartiméus, Doorn, Netherlands, 4 Department of Psychology, University of Pretoria, Pretoria, South Africa Author Note: Corresponding author: Ahmed Riaz Mohamed, Department of Psychology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa. Email: ahmed.mohamed@up.ac.za