This European Standard (EN 13757-1) specifies data exchange and communications for meters and remote reading of meters in a generic way. This European Standard establishes a protocol specification for the Application Layer for meters and establishes several protocols for meter communications which may be applied depending on the application being fulfilled. This is Part 1 of the European series of standards EN 13757. Other parts of EN 13757 are: EN 13757-2: Physical and Link Layer EN 13757 -3: Special application layer EN 13757-4: Meter reading via radio (remote reading of meters in the SRD band) EN 13757 -5: Relaying EN 13757-6: Local bus system. The main use of EN 13757-1 is to provide an overview of the protocols to be used at the different levels and to provide a specification for the COSEM-based application layer for meters (COSEM Companion Specification for Energy Metering). The primary focus is on providing unique combinations of generic interfaces and services to meet market and technology requirements through open architecture, interoperability and flexibility for innovation. This standard is intended for meters that have a limited energy supply (for example, battery-operated meters) available for operation and/or communication, but is not limited to this type of meter. This document (EN 13757-1:2014) has been prepared by the Technical Committee CEN/TC 294 "Communication systems for meters", the secretariat of which is held by DIN (Germany). Working Committee NA 041-03-66 AA "Communication systems for meters and their remote reading (SpA CEN/TC 294)" at the DIN Standards Committee Heating and Ventilation Technology and their Safety (NHRS) is responsible for preparation of the German language version.