 Formation damage can cause significant problems in oil and gas production and injection operations. To address this issue, it is important to understand how formation damage occurs and develop methods to accurately measure its extent. This paper reviews existing techniques for diagnosing, quantifying and disaggregating formation damage. These techniques are intended to help identify potential sources of damage and provide a more accurate assessment of the amount of damage present. By understanding the nature of formation damage, we can better design strategies to mitigate its effects and optimize remedial efforts. This article was authored by Oscar E. Medina, Juan P. Costano, Korea, Cristina Carvales and others.