Black Lives Matter (BLM), an international social movement, formed in the United States in 2013, is dedicated to fighting racism and anti-Black violence, especially in the form of police brutality. The name Black Lives Matter signals condemnation of the unjust killings of Black people by police (Black people are far more likely to be killed by police in the United States than white people) and the demand that society value the lives and humanity of Black people as much as it values the lives and humanity of white people. Have they been effective, I would say no. What has changed, is not much.