This study is about understanding **freezing of gait (FOG)**, a walking problem that often happens in Parkinson's disease. In this research, participants with Parkinson's or similar conditions will not receive new treatments but will continue their regular care from their doctors. The study will gather information over three years using questionnaires, walking and balance checks, video recordings, and other tests during regular doctor visits. - **Study Length:** Up to 36 months with follow-up visits. - **No New Treatments:** Participants continue their usual medical care. - **Eligibility:** Ages 30-85, with gait issues, willing to provide consent. The goal is to learn more about FOG, help predict fall risks, and aid future research. Participants should be able to do walking and balance tasks, either alone or with help, and be willing to share video and speech data. This study hopes to improve understanding and management of gait and balance disorders.