Contents I. Introduction 415 II. Reaction Mechanism 416 III. Scope and Limitation of the Reaction 417 A. Alkyl Halides 418 B. Tricoordinate Phosphorus Reactant 420 C. Effectiveness of Catalysts 421 IV. Synthetic Applications 421 A. Synthesis of Phosphonates 421 B. Synthesis of Phosphinates 422 C. Synthesis of Tertiary Phosphine Oxides 423 D. Synthesis of Phosphonyl and Phosphinyl Halides 424 E. Other Synthetic Applications 424 V. Behaviour of Sulfur and Fluorine Analogues under Arbuzov Conditions 425