Well Testing is recognised by many operating oil and gas companies to be the most hazardous operation they routinely undertake. Therefore, it is of great importance that such operations are extremely well planned and executed. This handbook covers all the major "Operational Aspects of Oil and Gas Well Testing" and uses a structured approach to guide the reader through the steps required to safely and effectively plan a well test operation under just about any circumstances world wide. Safety procedures and well testing recommended practices are rigorously addressed in this book, as are the responsibilities of those persons involved in well testing operations. Perforating equipment, drill stem test equipment and bottom hole pressure gauges are discussed in detail in the book. There is also a very valuable section on sub sea equipment, an area often not well understood even by experienced engineers who may have been primarily involved with land or jackup rigs. A major part of the book is the detailed coverage of the equipment and instrumentation that makes up a surface well testing package. It also covers operational and testing related problems such as, hydrates, wax and sand, and offers the reader some possible solutions. There are useful chapters on sampling, onsite chemistry, coil tubing and nitrogen operations and basic stimulation as they relate to well testing. Finally there is an extensive section of appendices covering useful engineering calculations and there is a complete example of a detailed well testing programme.