BestAvailableTechniques(BAT) is an essential element in integrated pollution prevention and control. Their application can present an opportunity to improve resource efficiency of production processes and achieve pollution reduction targets. In this paper,first present the applications that set emission limit values mainly based on best available techniques, and then describe the procedure and method to choose BAT. In the technology assessment process, there are many problems remained to solve because technological choices are multi-dimensional. For example, the best combination of technology is hard to determine and the economic viability is difficult to quantify. For these two aspects, this paper also introduces the research progresses of domestic and overseas scholars.