The present document specifies the CAMEL Application Part (CAP) supporting the fourth phase of the network feature Customized Applications for Mobile network Enhanced Logic. CAP is based on a sub-set of the ETSI Core INAP CS-2 as specified by ETSI EN 301 140 1 [26]. Descriptions and definitions provided by ETSI EN 301 140 1 [26] are directly referenced by this standard in the case no additions or clarifications are needed for the use in the CAP.