The paper describes Statoils experiences in drilling extended reach (ERD) wells, to primarily serve remote parts of widespread reservoirs and experiences in drilling horizontal and complicated wells, specially designed for optimal drainage of complex reservoirs. Several world records in exteded reach drilling, conducted from the Statfjord "C" platform are summarized. The latest ERD well drilled has a horizontal reach of 7290 m.

Included are also the latest plans of implementing these technics in developing new fields.

A brief summary is given on the achievements within the industry regarding other special well types, such as dual lateral, snaky, multiple arm, etc.

Furthermore the paper describes technical challenges of drilling complex wells and how planning is done to cope with these challenges.

Some limitations to the drilling are highlighted and solutions to drilling problems related to torque, drag, buckling, hole cleaning and surveying are given.

Cost-Benefit considerations regarding ERD, horizontal and complex wells are discussed.

Reducing number of platforms and/or leave out subsea templates due to ERD wells are considerable cost reducing factors.

Reducing the total number of wells from a platform due to horizontal and/or complex well profiles is another major cost reducing factor.

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