Today, volatility, uncertainty, ambiguity, and complexity are increasing in all kinds of situation, including human society, social systems and natural environment, making it difficult to predict the future. Before an unfavorable situation occurs, we will study how to explore the weak signals from big data, how to extract signs, how to interpret sign, how to make structured information from signs, how to make decisions on sign information, how to deliver predictor information, and create “Sign Studies" as a science that integrate them.