The ARTFL LEFFTDS Longitudinal Frontotemporal Lobar Degeneration (ALLFTD) study is a research project that looks into a brain condition called *Frontotemporal Lobar Degeneration* (FTLD). This condition affects parts of the brain responsible for decision-making, behavior, and language. The study has two parts: a **longitudinal arm** and a **biofluid-focused arm**. The longitudinal arm involves yearly check-ups using different tests and scans, while the biofluid-focused arm mainly collects blood and other samples. Participants can be people with a family history of FTLD or those with symptoms, but no known family link. The study looks at different types of FTLD, including Progressive Supranuclear Palsy (affects movement), Primary Progressive Aphasia (affects language), and others. People with other health issues like Alzheimer's, brain tumors, or severe alcohol problems can't join the study. **Key Points:** - The study involves annual visits for comprehensive assessments. - Participants can be from families with FTLD history or have symptoms without family history. - Exclusions include other brain diseases or severe health conditions. For more information, visit ALLFTD website.