For succesful herd management, identification and registration is very important. The most elementary form is freeze branding or tatooing in combination with manual registration. Other options are eartag, electronic eartag, electronic bolus,electronic implant, leg band, collar transponder or leg transponder. All electronic forms of ID can be read by a reader and send to a herd management computer program which in part can send and receive information from the milk metering device. This way the herd management system can play an active roll in the decision making process and produce attention lists. This information can also be send to the herdbook organisation.