Abrahamson and Trninic contribute to the KAIA agenda without being a priori 'affiliated' so to speak with either knowledge analysis (KA) or interaction analysis (IA) perspectives. a 'natural descriptive' approach (ND) perhaps more prominent in IA seeks to fill out understanding within a single level, that at which a phenomenon of interest appears to people. Abrahamson and Trninic's chapter aims to put in dialogue dynamical-systems and sociocultural theories of conceptual genesis. They focus on the relationship between motor-skill development and conceptual development, attending in particular to the way motor-skill development is supported by representational and social infrastructure. Umphress proposes that both caregivers in their everyday interaction with children and clinical interviewers are skilled knowledge practitioners (SKPs) 'adults whose work includes understanding and developing children's knowledge and thinking'. Kapon argues that the gesture originally served the subject as a simulation invoking and allowing the consideration of a non-verbal element of knowledge a phenomenological primitive (p-prims).