A medicament delivery device wherein a drive mechanism comprises a first resilient member 91 and a delay plunger rod assembly； wherein the delay plunger rod assembly comprises a proximal plunger 96, a distal plunger 90, a chamber 95 formed between the proximal and the distal plungers, an aperture, and delay means contained within the chamber； the distal plunger being positioned and configured in relation to a hold and release mechanism such that, as the drive mechanism exerts a pressure on the medicament container, the distal plunger acts against the delay means whereby a release of a signal generating member is delayed after the release of the drive mechanism to allow remaining contents of medicament in a medicament container to be completely expelled before the signal generating member is released.
