The Conceptual Model for Performance in Handwriting views that handwriting is important for one’s work and/or education domains of occupations. It considers the performance components, performance areas (functional performance), performance contexts, and the interactive relationship among them. Prerequisites to handwriting include performance components in sensory, perceptual, motor cognitive, and language functions, as well as integrations of these components. During evaluation, therapists can consider the three areas including biomechanical and ergonomic factors (e.g., sitting posture, pencil grip), quality of writing (e.g., leveling, directionality, spacing), and observation/other consideration (e.g., associated reactions and behavioral responses). This model illustrates that the interaction between performance components and functional performance in handwriting. For example, a child’s difficulty in quality of writing (functional performance) could be related to underlying cognitive function (performance components). Assessments include examining work samples, discussing with teachers and parents, reviewing educational record, directly observation, evaluating functional performance, and assessing any suspected interfering performance components. Standardized assessments including handwriting profile is used. Interventions with various treatment approaches can be used for individuals with handwriting difficulties; they are remedial (e.g., sensory integrative therapy), functional (e.g., biomechanical and ergonomic interventions), compensatory (e.g., use of audio-tape), adaptive (e.g., reduce amount of coping task), management (e.g., motivational approach), and maintenance (e.g., high power information technology appliance), to address the underlying deficits that interfere with successful handwriting.