Abstract This document presents the development and results of a study for determining the possible reasons of casing collapse in the Casabe Field, Colombia, specifically in block VI, where the phenomena occurred with more intensity. The study was requested as part of a revitalization strategy for this mature field, to maintain and improve the production performance of new and existing wells. The study consisted of different phases: Statistical and Probabilistic: firstly related to trend identification (i.e. well type, drilling date, well status and collapse localization), and secondly reliability and failure curves were created using the probabilistic Montecarlo analysis.Mechanical Integrity: casing integrity was analyzed using a software application called TDAS, by taking into account the corrosion effect and different operational and typical loads.Water flooding effects were also analyzed to take into account the stresses created by water injection on the casings at different formation levels (A or B). Figure 1 shows the four main phases that comprised the study. As a result of this study, a new well mechanical design was created and successfully applied on all new wells drilled in the Casabe field with zero collapse occurrences. Well longevity has been guaranteed, improving the economics of the field. The study gives a safety operational procedure considering a range in different parameters (tension, fluid level, corrosion, injection pressure and type of casing) that give support to critical well operations in order to mitigate casing collapse.