Parkinson's disease (PD) is a neurological condition, which affects the brain. Some symptoms of PD are tremors, stiffness, and slowness of movement. The purpose of this study is to assess how safe and effective ABBV-951 is in treating participants with Parkinson's disease in real world setting.

ABBV-951 is an approved drug being developed for the treatment of PD in Japan. Approximately 250 adult participants over 15 years with a diagnosis of PD who are prescribed ABBV-951 by their physicians will be enrolled in this study across Japan.

Participants will receive ABBV-951 as prescribed their physician and followed for 52 weeks.

There is expected to be no additional burden for participants in this trial. Study visits may be conducted on-site or virtually as per standard of care.

Inclusion Criteria:

• Diagnosed with advanced Parkinson's disease (aPD).
• Prescribed ABBV-951 as physicians' decision according to the approved label for treatment of aPD.
• Given informed consent (or by her/his legal representative, if it's a requirement from the participating hospital/clinic) for participating this study.

Exclusion Criteria:

• Prior treatment with ABBV-951 for PD.
• Currently participating in interventional clinical trials.

Adult participants who are prescribed ABBV-951 for the treatment of advanced Parkinson's disease (aPD).