Methods and apparatus for supporting targeted advertising and/or other targeted applications in set top boxes which use data and/or applications, e.g., EBIF (Enhanced TV Binary Interchange Format) applications, are described. Application level targeting is supported in which an application running on different STBs presents different application behavior and/or presents different visual sub-elements depending on the content of a subscriber profile on the particular individual STB. In the case of addressability at the Application Layer an EBIF application can target different viewers by checking private User Preference Items at runtime. Addressability at the signaling/platform level is also supported allowing targeting of a specific application or a sub-element within an application to a specific target group. In this scenario the particular applications/sub-elements are loaded on the set-tops that belong to a target group, e.g., satisfy targeting constraints specified in private targeting metadata that is received in an MPEG stream.