Chemical weapons present an excellent example as how a man can use his scientific and technological achievements against the society. This paper describes the notion of chemical weapons as well as historical review of its use. What is also described is the division of chemical weapons and chemical and physical features, medical aspect and legal regulation are showed too. The case of terrorist attack in Japan 1995 is being showed and situation in Karlovac during the Croatian war of independence is being described. The accent is put on the protection from the chemical weapons, personal and collective protection, water and food protection and protection on the national level. At the end of the paper a vision of using these weapons in the future is being given. This vision is based on the facts form the past and present situation.