There are two basic types of movement disorders. Some cause excessive movement, some cause slowness or lack of movement. Some of these are caused by mutations in genes. On the other hand, dementia is a condition of declining mental abilities, especially memory. Dementia can occur at any age but becomes more frequent with age. Researchers want to study the genes of families with a history of movement disorders or dementia. They hope to find a genetic cause of these disorders. This can help them better understand and treat the diseases. This study will not be limited to a particular disorder, but will study all movement disorders or dementias in general. This study will perform genetic testing to identify the genetic causes of movement disorders and dementia. Today, genetic testing can be done to analyze multiple genes at the same time. This increases the chances of finding the genetic cause of movement disorders and dementias.