Dr Rundle is a consulting paediatrician who has specialised in child development, particularly sleep disorders, for over 25 years. She provides private consultations at her home or at her client's home if appropriate. She also attends a NHS clinic at St Mary's Hospital, Paddington in Central London and at a child behaviour clinic in Richmond-upon-Thames in Surrey on the edge of Southwest London.

She has worked in the National Health Service for 30 years and has specialised in child health and development, including behaviour problems. Dr Rundle is a counsellor with special training to enable her to work with children following traumatic events such as the loss of a parent or other family member, or separation.

Dr Rundle is a graduate of Cambridge University and St Mary's Hospital Medical School. She has a post graduate Diploma in Child Health.