The paper deals with the problem of monitoring reliability issues in embedded systems. In particular, we concentrate on data reported during development, testing, operation in the field and service. For this purpose a special tool has been developed which provides the capability to collect data on-line and perform various analyses. The usefulness of this approach has been illustrated for some real embedded systems produced and serviced for several years in a commercial company. We present the interpretation of the obtained results, which proved their practical significance.