This book provides new insight into how learned skilled movements are affected in a disease with basal ganglia damage. The first aim was to examine the different types of praxis errors made by individuals with Parkinson’s disease(PD) in reference to other populations that experience apraxia. Apraxia by definition cannot be caused by weakness, sensory loss, or lack of comprehension, therefore the second objective of the study was to detect apraxia while remaining true to these prerequisites. The third objective was to extend the examination of apraxia beyond the upper limbs to investigate lower limb apraxia. In summary, these studies showed while not clinically present in all individuals with PD, apraxia is often featured in both the upper limbs and lower limbs, and is observable even in the presence of motor symptoms. A newly developed assessment tool for examining apraxia in the lower limbs was also introduced and found to be insightful and should be considered for assessment in other populations such as stroke. The results have supported the notion that apraxia assessments should be taken into account in the diagnosis and treatment of PD and other basal ganglia disorders.