Continued growth in worldwide demand for oil and gas has encouraged operators in Latin America to develop reservoirs using wells drilled from congested pads. Without remedial action, this practice would lead to operational or HSE risks, both on land and offshore. An oilfield service company has adopted a comprehensive approach to this issue by incorporating a methodology for planning and preventing the risk of well-to-well collisions while drilling in congested environments. This anticollision methodology has been used to drill thousands of wells in Latin America without the occurrence of collision events. Along with the anticollision methodology, the development and use of advanced surveying techniques allows the placement of complex horizontal and 3D wells in congested land and offshore fields. Multiple case histories support the functionality and effectiveness of the anticollision methodology. These case histories are from operations developed in different countries and include drilling in congested offshore environments. The focus of the methodology is safety of personnel and preventing HSE incidents.