The conventional and modern well test interpretation methods are an important tool in the petroleum engineer’s toolkit. Used in the exploration and discovery phase of a field, they are performed to determine the quality of a well or to permit estimation of producing rates at different producing pressures. However once a field enters the middle and later development phase, the reservoir flow environment grows increasingly complex and conventional or modern methods do not satisfy the needs of old field development and evaluation. Based on over 10 years of field and research experience, Streamline Numerical Well Test Interpretation Theory and Method provides an effective method for the determination of residual oil distribution for the middle and mature phases of a field. One of the most advanced books available, the author explains the development history of well test theory, analyzes the limitation of modern well test interpretation method, and proposes the concept and framework of numerical well test. This is quickly followed by an introduction of basic principles and solution procedures of streamline numerical simulation theory and method. The book then systematically applies streamline numerical well test interpretation models to a multitude of reservoir types, ranging from single layer reservoir to multi-layer reservoirs. The book presents multi-parameter streamline numerical well test automatic match interpretation method based on double-population genetic algorithm, which lays the foundation to fast automatic match of numerical well test. The book introduces streamline numerical well test interpretation software with independent intellectual property right which is programmed based on the above theoretical studies.