Occupational therapists consider in-hand manipulation (IHM) to be an important component of fine motor skills and to be related to handwriting and self-care proficiency. These relationships have not been well explored nor has the impact of intervention including IHM skill enhancement on proficiency in motor tasks. We propose that the existing conceptualisation of IHM may contribute to a dearth of evidence in this area. This paper closely examines the existing classification systems of IHM. We propose an adaptation of Exner's classification system which contains more discrete categories of IHM movements and includes: finger-to-palm translation to achieve stabilisation, palm-to-finger translation, simple shift, complex shift, simple rotation and complex rotation. Further research to test this modified classified system and to explore evidence for IHM intervention is warranted.