The 2018 budget proposed by President Trump for institutions of scientific research sees crippling and severe cuts. 20% here, 30% there, and in other cases budget cuts of 50% and more. So what to do? Scientists gathered in Boston in February to discuss the best response and how they might defend science and scientific integrity in the age of President Trump. This weekend sees coordinated marches in more than 50 countries and in cities and towns all over Australia where scientists and the community will stand up for science.