Checking the quality of a blast may be considered as subjective. Checking this quality will require measuring objective parameters. One of them is the resulting fragmentation of the blasted product. Numerous fragmentation measuring' systems have been developed and marketed, based on image-processing. This presentation of FragScan will illustrate advantages and difficulties when using such a system. FragScan is essentially defending a policy of large and representative sampling. The purpose is to show how fragmentation is discriminating both productivity and profit of quarry operations on a blast-by blast basis. The next step will then be to drive' the blasting process to reach a better' fragmentation. Other applications require the fragmentation as an essential result: this is the case for large boulders used in structure-reinforcement. Several case-studies have shown that FragScan can be used for quality-control, checking size-distribution of the product according to the requirements of the end-user. Only clear thinking about the precise use of such a measurement' will further the success of this task.