The diagnosis of PD requires a comprehensive evaluation by a healthcare professional experienced in movement disorders, incorporating clinical judgment, symptom assessment, and supportive diagnostic tests as needed. Early diagnosis is crucial for initiating appropriate treatment and supportive care to improve outcomes and quality of life for patients with PD. Diagnosis of PD is primarily based on clinical evaluation, including assessment of motor symptoms, medical history, and neurological examination. While there is no definitive test to diagnose PD, healthcare professionals use established criteria and a combination of diagnostic tools to make an accurate diagnosis. A detailed physical examination is performed to evaluate motor function, including assessment of tremor, bradykinesia (slowness of movement), muscle rigidity, and postural stability. Non-motor symptoms, such as cognitive impairment, psychiatric symptoms, autonomic dysfunction, and sleep disturbances, may also be assessed during the evaluation. Response to dopaminergic medications, particularly levodopa (L-dopa), can provide supportive evidence for the diagnosis of PD. While neuroimaging is not typically required for diagnosing PD, it may be used to support the diagnosis and rule out other conditions that can mimic PD. Structural neuroimaging techniques such as magnetic resonance imaging (MRI) may be used to exclude other causes of parkinsonism, such as tumors or stroke. Functional imaging techniques such as dopamine transporter (DAT) imaging with single-photon emission computed tomography (SPECT) or positron emission tomography (PET) can assess dopamine transporter activity in the brain, which is typically reduced in PD.