An experimental setup was built at the University of Tulsa to study buckling and postbuckling behavior of pipes constrained in straight horizontal and curved wellbores, Experiments were conducted to investigate the axial force transfer with and without static internal pressure. Different stages of buckling phenomena and their relation to the axial force, the pipe diameter (1/4 and 3/8 in.) and the pipe end-support conditions have also been investigated. Experimental results have shown that the buckling load is a strong function of the pipe diameter and the pipe end-support conditions. Static internal pressure appears to have insignificant influence on the buckling behavior of pipes, A brief review of recently developed mathematical models to predict buckling behavior of pipes in inclined, curved, and horizontal sections of wellbore is also presented Applications of the current theory are presented by using recently developed computer simulator. Results of the theoretical analysis have confirmed the versatility and effectiveness of computer simulator for better understanding and solving buckling related problems in the field. [S0195-0738(00)00903-1].