Late last month, the Texas DOT posted a message on X (formerly Twitter) urging cyclists to behave better. But this message garnered at least 250 frustrated responses. The echo chamber of X obviously is not a representative sample, but the backlash reflects real challenges that cyclists face every day. Unfortunately, people who bike—along with those who walk, take transit, or face other mobility issues—experience a world where most drivers do not follow the rules, which often puts them at a dangerous disadvantage.