The present invention relates to a medicament delivery device. The medicament delivery device may include an operation member configured to act on a medicament container for expelling a medicament. The device may configured to hold the operation member in a pre-tensioned state. The device may include an activation member configured to interact with the operation member to release it from the pre-tensioned state. The device may further comprise feedback. For example, the feedback may include generating an audible and/or tactile and/or visual signal indicating that the medicament has been completely expelled.