Abstract: Depth-of-penetration tests are used to compare a number of different ceramic types when impacted by tungsten and tungsten-carbide-cored ammunition. These results are then compared to ballistic limit test results on commercial armour systems incorporating the same set of ceramic materials and using high-hardness steel or aramid composite backings. The depth of penetration test are shown to broadly predict the performance of the ceramics when subsequently used in practical ceramic armour systems although penetrator erosion is also shown to be a significant factor which needs to be taken into account.