An FMEA is a systematic technique for establishing the effects of potential failure modes within a system. The analysis can be performed at any level of assembly. This can be done with a criticality analysis, in which case it is called an FMECA.

FMECA is a semi-quantitative analysis, where the failure probability and the consequence data are used to assess the criticality of each failure mode. It is a systematic methodology to increase the inherent reliability of a system or product. It is an iterative process of identifying failure modes, assessing their probabilities of occurrence and their effects on the system, isolating the causes, and determining corrective actions or preventive measures. When the analysis is done from a functional standpoint, it is usually performed at a plant or unit level, whereas if the focus is on the hardware, it usually descends down to the maintainable-item level. The amount of data required is different depending on the focus.