Abstract Testing gas wells in the southern North Sea area can be a time consuming affair, often involving fracture stimulation. Since a good assessment of reservoir characteristics and long term well productivity are essential design parameters in any development plan, test analysis, including post fracture test analysis, is of great importance. BP's extensive experience over recent years in the southern North Sea area has led to the development of a practical approach to well testing, which provides great flexibility yet has proven to be very reliable. The design philosophies and details are discussed in this paper along with the hardware which incorporates some of the latest Flopetrol developments, such as the EZ Valve™, MUST™ AND COMPUTEST™ data acquisition system. Some of the more important advantages are considered with respect to actual tests performed.